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Weather Station Hardware => AcuRite Weather Stations => Topic started by: wxwatching on July 05, 2016, 03:20:28 PM

Title: 5n1 Humidity Sensor Replacement
Post by: wxwatching on July 05, 2016, 03:20:28 PM
I own the 5n1 with the 1036 display. The humidity sensor has been giving bad readings for a couple of months but I am about 5 months past the warranty. This is not the new 5n1 that has a modular design which allows the temp/humidity sensor to be replaced easily. I am wondering if the replacement sensor they sell for the newer 5n1 can be made to work in the older one with a little soldering work. Anyone familiar with the inside of the 5n1?

Regards,
AB
Title: Re: 5n1 Humidity Sensor Replacement
Post by: vreihen on July 05, 2016, 05:38:10 PM
I would check and see if they will good-will warranty it anyway.  At one point, there was a defective humidity sensor in a whole batch, and they covered everyone's replacement 5-in-1 no matter how long they had it.....
Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on July 05, 2016, 05:59:55 PM
I own the 5n1 with the 1036 display. The humidity sensor has been giving bad readings for a couple of months but I am about 5 months past the warranty. This is not the new 5n1 that has a modular design which allows the temp/humidity sensor to be replaced easily. I am wondering if the replacement sensor they sell for the newer 5n1 can be made to work in the older one with a little soldering work. Anyone familiar with the inside of the 5n1?

Regards,
AB

I have a new 5n1 unit handy, but I don't know if has the new/replaceable temp/humidity sensor setup.  I'll open it up later and take a look, but I'm guessing you could make it work assuming they haven't moved to a different type of sensor chip.

If I remember correctly, there are only 4 wires between the main board and sub-assembly to worry about.  Some people have replaced the chip itself.  Others have used a compatible chip mounted on a SparkFun board and improvised its mounting in the wind tunnel. 

Which way you go it depends on if the chip alone has gone bad, or if the circuit traces on the sub-assembly mounting board have deteriorated.  If it's just trace deterioration, some have simply jumpered around the bad spots with success.



Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on July 05, 2016, 06:53:39 PM
OK.  I opened up the new 5n1.

Clearly Acurite has been busy.  The new main-board appears to have been revised in May of 2015.
 
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The second pic is of the replaceable SHT21 module.  It also seems to be from May 2015, so I guess it's not so "new".  Perhaps they just spent a year testing it.  It does seem to have a more robust-looking coating.  The circuit traces are no longer immediately evident.

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The third pic shows how the new module connects to the main board. 

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The fourth pic is a close-up of the SHT21 chip.

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Title: Re: 5n1 Humidity Sensor Replacement
Post by: DoctorKnow on July 05, 2016, 07:22:47 PM
Looks like they changed the wind magnet reader to me also. Mine doesn't look like that.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on July 05, 2016, 08:16:56 PM
Looks like they changed the wind magnet reader to me also. Mine doesn't look like that.

It's basically the same as it was, but the reed switch mounted differently.  As far as the wind cup assembly is concerned, the reed switch still looks to be in the same place, just under the black plastic internal cover.

If I recall correctly, the older design attached the reed switch to the upper plastic module, then was connected to the main board by a thin ribbon cable.  What bugged me about that setup is that it was too fragile when you had the 5n1 disassembled.  One klutzy move and you could break the solder joints.  (see pic attached below... it's the ribbon cable going out at the top)

This new mounting eliminates that problem as it's all part of the main board section.  I imagine it makes for faster/easier assembly in the factory, too.  The tripod mounting does look odd, though.

Another thing that looks different is the 433MHz antenna mounting.  It appears the antenna and radio circuitry are now part of the main board instead of being on a separate module.  I'd guess that also makes factory assembly quicker and easier.

I just found a pic of the old assembly.  Note how much more complicated the humidity temp/sensor was than the new module.  The new module should allow for a bit better airflow and fewer places for bugs to wedge themselves in.  Again, it's also probably easier/cheaper to manufacture.

Now that the module is user replaceable without soldering, perhaps an "upgrade" to a SHT31 chip could be made available. 

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Title: Re: 5n1 Humidity Sensor Replacement
Post by: DoctorKnow on July 05, 2016, 08:21:32 PM
I agree about the old reed switch. I still have my original unit just like the one you pictured above.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on July 05, 2016, 11:35:10 PM
I found a pic of the older SHT21 module.

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And here again is the new one.

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To answer the original question, I'm pretty confident you should be able to make the new module work in an older 5n1, provided it has a main board dated at least April 2012. 



Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on July 06, 2016, 12:37:59 AM
I found a link to the new humdity/temperature sensor with price. 

$10 isn't bad.

https://www.acurite.com/temperature-and-humidity-sensor-replacement-for-5-in-1-weather-sensors.html
Title: Re: 5n1 Humidity Sensor Replacement
Post by: wxwatching on July 06, 2016, 09:11:32 AM
I spoke with Acurite Support a couple of times regarding the humidity sensor problem, but they never offered to do any "good-will warranty" and I didn't press the issue. Since purchasing my 5n1 in February of 2015, they have had to replace my display console and fan due to failure. Those failures came under the warranty period, but the humidity issue seemed to developed just beyond it. I have no reason to complain about their support as they have appeared helpful. Just a little disappointed that I experienced several failures in the course of 1 year and 5 months ownership, but I'm sure it happens.

Anyway, I have not been able to see any of the picture attachments. Not sure what I need to do to view those.

I would be willing to purchase their current temp/humidity sensor replacement part and try to get it to work in my 5n1. I'm just weighing whether that is a viable option versus just replacing the entire 5n1. I asked Acurite if such was possible, but obviously they were unable to confirm or deny such a possibility.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: wxwatching on July 06, 2016, 09:12:18 AM
Ok, I see the pics now. Not sure why I couldn't before.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on July 06, 2016, 11:32:35 AM
I saw a couple of pictures on Acurite's site that can help determine if you have one of the newer 5n1 sensors that are compatible with the replaceable module.

One has to do with the configuration of the Acurite logo.  The other has to do with the location of the A-B-C channel switch.

But as I said earlier, it shouldn't be hard to make the replaceable module fit an older unit if you're willing to solder. 

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Title: Re: 5n1 Humidity Sensor Replacement
Post by: wxwatching on July 06, 2016, 11:40:57 AM
Yes, I saw that on Acurite's site. I have the older unit. If I get an opportunity this weekend, I will open it up and see what the possibilities are. The pics you posted does make it look promising.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: wxwatching on July 13, 2016, 10:52:39 PM
I ordered the replacement sensor Acurite sells (https://www.acurite.com/temperature-and-humidity-sensor-replacement-for-5-in-1-weather-sensors.html). Acurite makes the following note about this replacement:

Quote
*NOTE: Legacy versions of the 5-in-1 Sensor are not compatible with this replacement. Compatible sensors have a black box printed under the AcuRite logo that says, "5-IN-1 WEATHER".

However, it does appear to be compatible if you are willing to do a little soldering. In the picture, you will see I put a connector on the board where the old sensor cable was soldered to the board. I happen to have a compatible connector on another piece of equipment that was no longer working, so I robbed it and put it on.

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After that, I simply plugged in the replacement sensor and all seems to be well thus far. My external humidity reading is in line with the indoor humidity sensor at the moment as I have the 5n1 inside my house beside my 1036 display console. I plan to keep it inside overnight and check in the morning to see if the external temp/humidity stays in line with the indoor sensors.

Also, the pic shows the connector as I originally soldered it on the board. I wasn't able to fully seat the black cover back on, so I redid it and placed it at more of an angle so now the black cover goes on as it should.

Perhaps this will help someone else if they have an older version of the 5n1 and don't want to yet replace the whole unit. Note how the red wire is oriented in relation to the connection to the board.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: wxwatching on July 13, 2016, 11:06:41 PM
By the way, here's a picture of the original and now bad temp/humidity sensor that I replaced - a 2013.06.18 edition.

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Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on July 13, 2016, 11:12:49 PM
By the way, here's a picture of the original and now bad temp/humidity sensor that I replaced - a 2013.06.18 edition.

Interesting.  I haven't seen that version before,
Title: Re: 5n1 Humidity Sensor Replacement
Post by: DangHumid on July 25, 2016, 04:35:31 PM
I would check and see if they will good-will warranty it anyway.  At one point, there was a defective humidity sensor in a whole batch, and they covered everyone's replacement 5-in-1 no matter how long they had it.....

Hmmm, if only that were true. I have one of the earlier ones with a dead outside Humidity sensor. About a year back it died so I called and was told to buy a new 5-in-1 head for a hundred bucks. I signed up today to see if anyone had managed to get the old ones working with a hack or something as the temp and wind direction have now quit too.

Since I was going to have to pull it apart, I hoped I could get Humidity back, but after reading a bunch of new and old posts on the Humidity sensors, seems like I am not alone, so will donate this to the trash and look for a different brand that is supported with replacement parts. Should have bought the Davis back then, but price won out over good sense. :D

I have learned my lesson.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on July 25, 2016, 04:52:20 PM
I would check and see if they will good-will warranty it anyway.  At one point, there was a defective humidity sensor in a whole batch, and they covered everyone's replacement 5-in-1 no matter how long they had it.....

Hmmm, if only that were true. I have one of the earlier ones with a dead outside Humidity sensor. About a year back it died so I called and was told to buy a new 5-in-1 head for a hundred bucks. I signed up today to see if anyone had managed to get the old ones working with a hack or something as the temp and wind direction have now quit too.

Since I was going to have to pull it apart, I hoped I could get Humidity back, but after reading a bunch of new and old posts on the Humidity sensors, seems like I am not alone, so will donate this to the trash and look for a different brand that is supported with replacement parts. Should have bought the Davis back then, but price won out over good sense. :D

I have learned my lesson.

What lesson?

First off, if it's a very old 5n1, you can replace the humidity sensor with an equivalent part.  There is at least one very old thread here about that.

If it's a 5n1 from 2012 or so, you can replace the SHT21 with their current replacement module (about $10) and a bit of simple soldering.  There was a recent thread here about that (actually, this thread).

If it's a very recent 5n1, the module can be replaced without soldering at all.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: Scalphunter on July 25, 2016, 05:48:19 PM
Nine like he said he learned his lesson. I bought an accurate station before they came along with this new junk your so proud of. It didn't even make it thru an Alaskan winter. Even clocks coming from Chaney need to be taken apart to get the switches to set it to work. As to the wx station  I called your lousy support and was told they didn't support that station that I bought 6 months prior. One has better luck with OS supports then any support from Chaney. As far as Accurate is concert here the are to the Wx world to what a lot of fly by radios where during the CB radio craze. Any reputable  company would have honored their warranty but not yours. By the way just how much on the take are you with them now that Rhino disappeared.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on July 25, 2016, 05:50:51 PM
Nine like he said he learned his lesson. I bought an accurate station before they came along with this new junk your so proud of. It didn't even make it thru an Alaskan winter. Even clocks coming from Chaney need to be taken apart to get the switches to set it to work. As to the wx station  I called your lousy support and was told they didn't support that station that I bought 6 months prior. One has better luck with OS supports then any support from Chaney. As far as Accurate is concert here the are to the Wx world to what a lot of fly by radios where during the CB radio craze. Any reputable  company would have honored their warranty but not yours. By the way just how much on the take are you with them now that Rhino disappeared.

It's not a matter of being proud.  It's a matter of understanding what you're working with.

"My lousy support"?  I don't have any support, lousy or otherwise.

You are quite off-base scalphunter.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: DangHumid on July 25, 2016, 06:01:17 PM
First off, if it's a very old 5n1, you can replace the humidity sensor with an equivalent part.  There is at least one very old thread here about that.

OK, off to a good start here. Calling me a liar eh? I was TOLD by Customer Service that parts were no longer available. So, either I really AM lying -OR- CS were wrong -OR- CS was trying to be greedy and get me to pay another hundred bucks for the failed head.

I have read a few of your posts here and you seem to have a bit of a bullying approach. One catches more flies with honey than vinegar.

Now, to that "at least one very old thread here," it would be much more helpful to include a link to it since you are more likely to be familiar with the topic wording than this tired old fart and newbie to this website.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on July 25, 2016, 06:09:24 PM
First off, if it's a very old 5n1, you can replace the humidity sensor with an equivalent part.  There is at least one very old thread here about that.

OK, off to a good start here. Calling me a liar eh? I was TOLD by Customer Service that parts were no longer available. So, either I really AM lying -OR- CS were wrong -OR- CS was trying to be greedy and get me to pay another hundred bucks for the failed head.

I have read a few of your posts here and you seem to have a bit of a bullying approach. One catches more flies with honey than vinegar.

Now, to that "at least one very old thread here," it would be much more helpful to include a link to it since you are more likely to be familiar with the topic wording than this tired old fart and newbie to this website.

Oh, good grief.  I'm sorry if my information offends you.  :roll:

Yes, there is an old thread here about the original chips they used in the sensor before they started using the SHT21.

If you had asked nicely, I might have searched for it for you, but now I'm not so inclined.

Remember what you said  One catches more flies with honey than vinegar."

Title: Re: 5n1 Humidity Sensor Replacement
Post by: tarheelbill on August 10, 2016, 02:55:08 PM
hi there everyone....i been reading this post because i have 2 5n1 sensors that humidity/temp sensor is bad. ive been through 4 different 5n1 sensors, with which i will say acurite has been very good in replacing. i even had rhino a few years back send me some parts to try and repair the older version of these sensors, where the temp was separate from humidity but didnt have success. my question to yall is both of my 5n1's have the sht21 sensor but not the quick connect plug. the oldest one dates to 04/10/2012 on temp/humidity board. the part number on main board is VN1A2-V1 and the part number on temp/humidity board is VN1K1A2-V1. ihavent looked at other sensor yet but it is one acurite replaced before and its newer than this one. do yall think the replacement temp/humidity sensor for 10 bucks will work on both of mine? if not is there another sensor i could buy to replace both? im truly hoping though that these will work but just like to know before buying. im an electronics tech so no issues there in soldering, pluse i dont have the female part of the plug but i can just cut the plug off new sensor and solder it directly to main board. please let me know what yall think and i truly appreciate everyones help.

p.s. i saw the pictures of the outside indications of compatible and incompatible sensors neither one of mine have the 5n1 printed under acurite nor is my abc switch stepped down like the newer ones. but i still have hope by what wxwatching showed when he replaced his sensor on older unit.  :-)
Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on August 10, 2016, 03:06:31 PM
hi there everyone....i been reading this post because i have 2 5n1 sensors that humidity/temp sensor is bad. ive been through 4 different 5n1 sensors, with which i will say acurite has been very good in replacing. i even had rhino a few years back send me some parts to try and repair the older version of these sensors, where the temp was separate from humidity but didnt have success. my question to yall is both of my 5n1's have the sht21 sensor but not the quick connect plug. the oldest one dates to 04/10/2012 on temp/humidity board. the part number on main board is VN1A2-V1 and the part number on temp/humidity board is VN1K1A2-V1. ihavent looked at other sensor yet but it is one acurite replaced before and its newer than this one. do yall think the replacement temp/humidity sensor for 10 bucks will work on both of mine? if not is there another sensor i could buy to replace both? im truly hoping though that these will work but just like to know before buying. im an electronics tech so no issues there in soldering, pluse i dont have the female part of the plug but i can just cut the plug off new sensor and solder it directly to main board. please let me know what yall think and i truly appreciate everyones help.

p.s. i saw the pictures of the outside indications of compatible and incompatible sensors neither one of mine have the 5n1 printed under acurite nor is my abc switch stepped down like the newer ones. but i still have hope by what wxwatching showed when he replaced his sensor on older unit.  :-)

Yes.  Wxwatching seems to have had success replacing the SHT21 with the new replaceable module (see earlier in this thread).
Title: Re: 5n1 Humidity Sensor Replacement
Post by: tarheelbill on August 10, 2016, 03:21:53 PM
hi nincehelser...thank you so much for such fast reply, that sounds excellent....heck im gonna order 2 of them and try and ill post back on my results. it would be awesome if i can get both units back up, thank you again and hopefully i can help someone by doing this too.  :-) :-) =D> =D>
Title: Re: 5n1 Humidity Sensor Replacement
Post by: wxwatching on August 10, 2016, 04:42:57 PM
I lean strongly to the belief that it will work in both your units. I certainly would give it a try. I am thinking that Acurite's incompatible warning is due to the fact that the older units do not have a socket on the board that you can plug their current temp/humidity replacement into, and they are probably not going to encourage individuals to do soldering work. Once the warranty is passed and something breaks, I see no reason in not trying to repair it on your own.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: tarheelbill on August 10, 2016, 11:08:12 PM
Hi wxwatching.... Thank you so much for responding and also for your help. Yes I totally agree about noncompatibility is most likely just the plug because the sensor is the same and same 4 wire hookup. I went ahead n ordered 2 sensors, so gonna give it a try. If you can could you possibly show the wire hookup that you did. It looks from your picture that the red wire goes to the far right solder joint...thstd if ur looking at the main board with the back of the sensor suite to the right. And I'm assuming that the other 3 wires just follow as arranged in the ribbon. Thank you again for all your help.   :grin:
Title: Re: 5n1 Humidity Sensor Replacement
Post by: wxwatching on August 11, 2016, 09:50:05 AM
If the 5n1 is oriented so that the main pcb board is at the top and the rain gauge at the bottom (which is how it is in the picture I took), then the four holes where you connect the cable will be oriented north and south. The red wire is in the most north hole. I don't know if your 5n1s are exactly like mine. I would suggest you trace the wire from your current temp/humidity sensor back to the main pcb board. The temp/humidity sensor should have markings for the wires showing VSS, VDD, SDA, and SCL. As I recall, SCL is the red wire. So, I would trace that back to the main pcb board and note which hole it is connected to. Then just be sure when you get the new sensor, you connect is the same way. In the end, if you connect the wires in reverse order, you will have very noticeably incorrect readings. If that happens, just reverse the wire order.

Easiest thing is to just trace the wires from your old sensor before you disconnect it and note on the main pcb board where the SCL connection is to be made and then make sure your red wire on the new sensor connects to that location.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: dschmidt_2000 on August 16, 2016, 12:50:57 AM
Mine died this weekend after 2.5 years.  Looked over at WUND and my readings were going from -20F to +130F.
Tried to reflow the chip but now it's stuck at -40F and 1% Rh. M

Went ahead and ordered a new 5 in 1 that now has the modular SHT21 board, but also bought some of these SHT21 boards from China to repair my old unit.
http://www.ebay.com/itm/1PCS-SHT21-Digital-Humidity-And-Temperature-Sensor-Module-Replace-SHT15-SHT11-/182103356189

This board has some components on the opposite side for level shift and pullups that I'll remove.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: DangHumid on August 16, 2016, 10:53:41 AM
Mine died this weekend after 2.5 years.

After being told they no longer carry replacement Humidity sensors for my two year old 5-in-1 and the "simple answer is to buy another 5-in-1" I decided to spend my money elsewhere. That has saved me $97.77 and I have a much better display as a bonus.

Arduino Nano $3.20 (5 for $16)
DHT22 $0.36 (10 for $3.60)
433MHz radio receiver $1.67 (6 for $10)

Some code and an old 7" tablet I no longer use and this is what you get. While testing I actually used a 20 x 4 line LCD screen ($7.99) I had in my junk drawer.

The open space to the right of the Temp/Humidity/Rain is where I am just writing the code for the Low/High for the Month and Year for Temps, Humidity and rain.

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Title: Re: 5n1 Humidity Sensor Replacement
Post by: dschmidt_2000 on August 16, 2016, 11:10:29 AM
Nice!  Good work there.
Now if you can get it to do an upload to WUND from the arduino I'm on board!

Did you wire in the anemometer and wind direction/rain sensors to your arduino?
Title: Re: 5n1 Humidity Sensor Replacement
Post by: DangHumid on August 16, 2016, 05:58:18 PM
Now if you can get it to do an upload to WUND from the arduino I'm on board!

Don't know what WUND is but the Ethernet shield allows Internet access.

Did you wire in the anemometer and wind direction/rain sensors to your arduino?

Nope, I intercept the radio transmission from the 4-in-1 (was 5-in-1 when it did Humidity :)) decode all the data with the Arduino nano, then send that (except the 99% dead Humidity) and the Temp and Humidity from the DHT22 to my home IoT network of nRF24 radios and Arduinos.

The little square in the top left of the tablet display indicates good/bad data. If it doesn't get valid data within 90-seconds that square turns red until it does get good data from the 4-in-1. Currently the 4-in-1 is sending about 30% valid data. Really pretty poor actually. In fact the 4-in-1 sends data streams twice in a row to try and assist that poor reliability. You don't notice transmission errors with the acurite desktop unit, but grabbing data to send to my IoT every thirty seconds highlights how poor it is. The 4-in-1 is only 60-feet, line of sight, from the Arduino, by the way.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: dschmidt_2000 on August 17, 2016, 12:14:24 AM
WUND is WeatherUnderground.

Nice! Where did you find info on decoding the RF stream?  I've got a thin-net PC running 24/7 just to do rapid fire updates to WUND. At 5 watts, isn't a lot of power but would love to get it even lower.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: DangHumid on August 17, 2016, 12:06:39 PM
Nice! Where did you find info on decoding the RF stream?

Online of course. Isn't everything online? :D

Here ya go, I have modified it a bit to keep down the time spent hogging interrupts as it drives my nRF24L01 radio network crazy. I can't find the original, but it was done by Jens Jensen and pretty sure 2015.

Code: [Select]
(c) 2015 Jens Jensen
#import <avr/eeprom.h>
#define SYNC_HI 675
#define SYNC_LO 575
#define LONG_HI 450
#define LONG_LO 375
#define SHORT_HI 250
#define SHORT_LO 175
#define RESETTIME 10000
#define PIN 2 // data pin from 433 RX module
#define MAXBITS 65 // max framesize
#define RESET 0 // no sync yet
#define INSYNC 1 // sync pulses detected
#define SYNCDONE 2 // complete sync header received
volatile unsigned int pulsecnt = 0;
volatile unsigned long risets = 0; // track rising edge time
volatile unsigned int syncpulses = 0; // track sync pulses
volatile byte state = RESET;
volatile byte buf[8] = {0, 0, 0, 0, 0, 0, 0, 0}; // msg frame buffer
volatile bool reading = false; // have valid reading
unsigned int raincounter = 0;
const float winddirections[] = { 315.0, 247.5, 292.5, 270.0,
                                 337.5, 225.0, 0.0, 202.5,
                                 67.5, 135.0, 90.0, 112.5,
                                 45.0, 157.5, 22.5, 180.0
                               };
#define MT_WS_WD_RF 49 // wind speed, wind direction, rainfall
#define MT_WS_T_RH 56  // wind speed, temp, RH

void setup()
{ Serial.begin(115200);
  Serial.println(F("Starting Acurite5n1 433 WX Decoder v0.2 ..."));
  pinMode(PIN, INPUT);
  attachInterrupt(0, My_ISR, CHANGE);
}

void loop()
{ if (reading)
  { noInterrupts();
    if (acurite_crc(buf, sizeof(buf)))
    { float windspeedkph = getWindSpeed(buf[3], buf[4]);
      int msgtype = (buf[2] & 0x3F);
      if (msgtype == MT_WS_WD_RF)
      { float rainfall = 0.00;
        unsigned int raincounter = getRainfallCounter(buf[5], buf[6]);
        float winddir = getWindDirection(buf[4]);
      } else
      if (msgtype == MT_WS_T_RH)
      { float tempf = getTempF(buf[4], buf[5]);
        bool batteryok = ((buf[2] & 0x40) >> 6);
      } else
      { Serial.print("unknown msgtype: ");
        for (int i = 0; i < 8; i++) {
          Serial.print(buf[i], HEX);
          Serial.print(" ");
        }
      }
    } else
    {
      // failed CRC
    }
    reading = false;
    interrupts();
  }
  delay(100);
}

bool acurite_crc(volatile byte row[], int cols)
{ cols -= 1; // last byte is CRC
  int sum = 0;
  for (int i = 0; i < cols; i++)
  { sum += row[i];
  }
  if (sum != 0 && sum % 256 == row[cols])
  { return true;
  } else
  { return false;
  }
}

float getTempF(byte hibyte, byte lobyte)
{ int highbits = (hibyte & 0x0F) << 7;
  int lowbits = lobyte & 0x7F;
  int rawtemp = highbits | lowbits;
  float temp = (rawtemp - 400) / 10.0;
  return temp;
}

float getWindSpeed(byte hibyte, byte lobyte)
{ int highbits = (hibyte & 0x7F) << 3;
  int lowbits = (lobyte & 0x7F) >> 4;
  float speed = highbits | lowbits;
  if (speed > 0)
  { speed = speed * 0.23 + 0.28;
  }
  float kph = speed * 60 * 60 / 1000;
  return kph;
}

float getWindDirection(byte b)
{ int direction = b & 0x0F;
  return winddirections[direction];
}

int getRainfallCounter(byte hibyte, byte lobyte)
{ int raincounter = ((hibyte & 0x7f) << 7) | (lobyte & 0x7F);
  return raincounter;
}

void My_ISR()
{ unsigned long timestamp = micros();
  if (digitalRead(PIN) == HIGH)
  { if (timestamp - risets > RESETTIME)
    { state = RESET;
      syncpulses = 0;
      pulsecnt = 0;
    }
    risets = timestamp;
    return;
  }
  // going low
  unsigned long duration = timestamp - risets;
  if (state == RESET || state == INSYNC)
  { if ((SYNC_LO) < duration && duration < (SYNC_HI))
    { state = INSYNC;
      syncpulses++;
      if (syncpulses > 3)
      { state = SYNCDONE;
        syncpulses = 0;
        pulsecnt = 0;
      }
      return;
    } else
    { syncpulses = 0;
      pulsecnt = 0;
      state = RESET;
      return;
    }
  } else
  { if ( pulsecnt > MAXBITS )
    { state = RESET;
      pulsecnt = 0;
      reading = true;
      return;
    }
    // stuff buffer with message
    byte bytepos = pulsecnt / 8;
    byte bitpos = 7 - (pulsecnt % 8); // reverse bitorder
    if ( LONG_LO < duration && duration < LONG_HI)
    { bitSet(buf[bytepos], bitpos);
      pulsecnt++;
    }
    else if ( SHORT_LO < duration && duration < SHORT_HI)
    { bitClear(buf[bytepos], bitpos);
      pulsecnt++;
    }
  }
}

Title: Re: 5n1 Humidity Sensor Replacement
Post by: tarheelbill on August 17, 2016, 03:46:52 PM
Hi wxwatching..... And also everyone else with temp/humidity sensor issues. I ordered the replacement parts available through acurite. Even though it has a 4 terminal connector and says it isn't compatible well guess what? It is the same but just improved circuit board. It still uses the sht21 sensor and I replaced 2 of them yesterday on 2 5n1 sensors and readings are actually more accurate than they ever been. The reason they apparently say the replacement part isn't compatible is because of the connector and that's it. So if you feel comfortable in doing a little soldering, you can save your 5n1. Again I wanna thank wxwatcher for the encouragement to try. And if anyone needs help with connections please let me know
😊😊
Title: Re: 5n1 Humidity Sensor Replacement
Post by: dschmidt_2000 on August 17, 2016, 04:11:16 PM
So if you feel comfortable in doing a little soldering, you can save your 5n1. Again I wanna thank wxwatcher for the encouragement to try. And if anyone needs help with connections please let me know
😊😊
Excellent! Can you tell me - are the traces now buried on an inner layer of the board vs on the top?

Also does the new board drop into the same mounting slots and fit well inside 5 in 1 housing?
Title: Re: 5n1 Humidity Sensor Replacement
Post by: tarheelbill on August 17, 2016, 04:45:34 PM
Hi dschmidt...... The boards still. Have traces on outside but definitely a new improved coating...more like a conformal coating. Definitely a hardier setup. The sensor is the same sht21. It.does fit In the same way. Your old sensor faced the rain Guage and this one will too. The big difference is this new sensor has a white connector on the wires for newer 5n1. But I just removed connector n soldered straight to main board like old sensor. But. I can already tell more accurate results. Maybe it's cause I was so use to false info... Lol. But I hope this helps and I'd definitely go for it. I give credit to wxwatcher for helping me. I'll help anyway I can.... Ty
Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on August 17, 2016, 05:47:48 PM
So if you feel comfortable in doing a little soldering, you can save your 5n1. Again I wanna thank wxwatcher for the encouragement to try. And if anyone needs help with connections please let me know
😊😊
Excellent! Can you tell me - are the traces now buried on an inner layer of the board vs on the top?

Also does the new board drop into the same mounting slots and fit well inside 5 in 1 housing?

If you go back to the start of this thread you'll find several pictures of the new modular sensor and how it fits into the wind tunnel.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: rct on October 17, 2016, 05:53:21 PM
I'm about to do the same repair.  The 5-n-1 has a soldered ribbon cable.   What's the collected wisdom on the best way to do it:

Thanks
Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on October 17, 2016, 06:05:32 PM
I'm about to do the same repair.  The 5-n-1 has a soldered ribbon cable.   What's the collected wisdom on the best way to do it:
  • replace jumper cable on the temperature sensor board with the ribbon cable coming from the main board?
  • replace the ribbon cable, after cutting the connector off, soldering to main board?
  • Solder a matching male connector (4-pin JST??) onto the main board?  (Anyone know the specific connector type/part?)

Thanks

Personally, I'd replace the ribbon cable.  That's mainly because they seem to be weakly soldered on the board.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: DoctorKnow on October 19, 2016, 01:42:32 PM
I decided to check mine out since my humidity is not going up & down like it should be compared to my acurite tower and Oregon 100. Everything looked really good, and I took a pic while I was in there. Not sure why the humidity is not going higher than 92% at night lately.

Title: Re: 5n1 Humidity Sensor Replacement
Post by: rct on October 21, 2016, 12:45:08 PM
I've somewhat successfully replaced the temp/humidity sensor in my 5n1 without the pins.   It's easy to see why the temp/humidity board failed since the traces have been eaten through.  See attached.  The new board looks pretty well sealed (lacquered?).   

I used new individual wires and replaced both ends.

George's warning about the fragile nature of the ribbon cable was very apropos, looks like I broke the wind speed sensor cable on reassembly, so now I need to take it all apart and do another repair.

Related note for another topic: I suspect I need to replace the fan motor, I think it's got too high of a resistance to get started, though runs once started.  Where are people getting the replacement motors from?

Thanks.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: rct on October 21, 2016, 12:55:43 PM
Forgot to mention a tip for others attempting the same repair.  The pins are in the same order on the replacement board.  Both have the pins labeled.  The pins on the exposed side of the main board aren't labeled but are in the same order as you would expect from using a ribbon cable.  The Vss pin is negative, the Vdd pin next to it is positive.  With a voltmeter, with the batteries installed in the 5n1, you should see ~2 -3 Vdc between the Vss pin and any of the other 3 pins. 

Title: Re: 5n1 Humidity Sensor Replacement
Post by: davefr on October 25, 2016, 02:36:35 PM
My 5 in 1 just failed for the same problem.

The root cause of the problem was not the chip.  It's the trace that had developed an open circuit from corrosion. I just soldered on a tiny shunt wire from the two pads on the circuit board and the problem was solved.  I sealed the other traces with lacquer.  It looks like AcuRite didn't do a very good job sealing that circuit board.

(https://dl.dropboxusercontent.com/u/59847735/P1070135.JPG)
Title: Re: 5n1 Humidity Sensor Replacement
Post by: rct on October 25, 2016, 03:04:13 PM
My 5 in 1 just failed for the same problem.  [...]  It looks like AcuRite didn't do a very good job sealing that circuit board.

FWIW, the replacement boards seem to be have a full lacquer coat, unlike the old boards which have none.   Glad you were able to repair yours.  The corrosion on mine was right near the chip so not easily fixable.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: nincehelser on October 25, 2016, 03:17:45 PM
My 5 in 1 just failed for the same problem.  [...]  It looks like AcuRite didn't do a very good job sealing that circuit board.

FWIW, the replacement boards seem to be have a full lacquer coat, unlike the old boards which have none.   Glad you were able to repair yours.  The corrosion on mine was right near the chip so not easily fixable.

They've been trying different coatings over the years, apparently with mixed success.  The latest version does look far more robust, though.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: Tangster1 on August 22, 2017, 01:18:10 PM
I just replaced my old board that died after just a bit past 3 yrs old with the new accurite board. Just snipped the plug off cut old ribbon tape at board slit the insulation to separate wires took hemostat removed old wires & remove  a little insulation of new blk and red wires on new board tinned them 1st and soldered them onto op board where i removed old wires from underneath station is working like a charm thanks for the pics and info guys really helped me

Oh and to add my board looked like new no corrosion or spotted traces did see one spot on top of board right were temp sensor was mounted a area were lacquer had popped or flaked off . I guess mine just went bad the bottom of the board was clean and green solid covered in epoxy I guess it is ?
Title: Re: 5n1 Humidity Sensor Replacement
Post by: daman on August 22, 2017, 06:09:01 PM
I saw a couple of pictures on Acurite's site that can help determine if you have one of the newer 5n1 sensors that are compatible with the replaceable module.

One has to do with the configuration of the Acurite logo.  The other has to do with the location of the A-B-C channel switch.

But as I said earlier, it shouldn't be hard to make the replaceable module fit an older unit if you're willing to solder. 

 [ You are not allowed to view attachments ]

 [ You are not allowed to view attachments ]
My 5n1 contradicts this information, my 5n1 logo says only "ACURITE" on the side and i DO have the replaceable module.
 
Title: Re: 5n1 Humidity Sensor Replacement
Post by: Tangster1 on August 23, 2017, 08:01:32 AM
 My older one I replaced board in got it new in May of 2014 did not have the newer logo when it went crazy 2 wks back I just brought a new one as I wanted a new color display anyways .

  The new one has that plug module of the Temp and humidity board were as the older one with just accurite in a little darker then unit logo on side didn't . I'm just guessing but maybe yours was one of the last runs of the older circuitry with newer housings ?

Title: Re: 5n1 Humidity Sensor Replacement
Post by: daman on August 23, 2017, 08:05:24 AM
You could be right? I was surprised to see it had the replaceable module when I had it apart last week cleaning it and checking for bugs.
Title: Re: 5n1 Humidity Sensor Replacement
Post by: Harry Nagel on May 09, 2022, 06:33:04 PM
I just replaced the temp and humidity board in my old 5 in 1. I used a bit of solder wick to remove the old one and attached a 4 pin jst connector to the board. It was working instantly. I picked up a jst connector kit from Amazon for a fe bucks. I no longer have -40F for outdoor temp.

Thanks muchly for this thread.