MH-Z19B - MHZ19: Unknown response: 0 0 0 0 0 0 0 0 0

Moderators: BertB, rtenklooster, Voyager, Stuntteam, Martinus

Message
Author
dgcracker
Normal user
Posts: 7
Joined: 19 Dec 2017, 11:06

Re: MH-Z19B - MHZ19: Unknown response: 0 0 0 0 0 0 0 0 0

#21 Post by dgcracker » 19 Dec 2017, 16:25

Thx for reply. I have loaded test file into nodemcu v3 and there is no change. Still can't read sensor values. Only in logs I see messages “MHZ19: Unstable reading, ignoring! PPM value: 776 ...." PPM and Temp in logs are changing but each read of sensor values report "Unstable reading....". Sensor red leds are blinking from time to time so it looks like sensor is OK. Any ideas?
Thank you for help!

timbiker
Normal user
Posts: 27
Joined: 09 Nov 2017, 11:37

Re: MH-Z19B - MHZ19: Unknown response: 0 0 0 0 0 0 0 0 0

#22 Post by timbiker » 19 Dec 2017, 18:01

dgcracker wrote:
19 Dec 2017, 16:25
Thx for reply. I have loaded test file into nodemcu v3 and there is no change. Still can't read sensor values. Only in logs I see messages “MHZ19: Unstable reading, ignoring! PPM value: 776 ...." PPM and Temp in logs are changing but each read of sensor values report "Unstable reading....". Sensor red leds are blinking from time to time so it looks like sensor is OK. Any ideas?
Thank you for help!
I already had this issue and T-Der answered me. That's because you have the B version of the sensor. Like me

You have to get the MH-Z19 plugin from the "2.0" branch of the Espeasy github

TD-er
Normal user
Posts: 838
Joined: 01 Sep 2017, 22:13
Location: the Netherlands
Contact:

Re: MH-Z19B - MHZ19: Unknown response: 0 0 0 0 0 0 0 0 0

#23 Post by TD-er » 19 Dec 2017, 20:26

You seem to have the "B" version of the sensor, which gives a "0" as S-value.
Starting version dev-13, this will be supported, but you can also compile a version for yourself if you need it faster.
I don't think the new dev-13 release will take long, since the last 2 days, a lot of pull requests were merged and I think it is only testing for a (short) while with these new versions before the new release will be created.

dgcracker
Normal user
Posts: 7
Joined: 19 Dec 2017, 11:06

Re: MH-Z19B - MHZ19: Unknown response: 0 0 0 0 0 0 0 0 0

#24 Post by dgcracker » 19 Dec 2017, 21:26

Thx for reply and help. Exactly I have "B" version. So I have to wait for dev-13 or in the meantime compile it myself :)

dmq
Normal user
Posts: 14
Joined: 09 Dec 2017, 19:15

Re: MH-Z19B - MHZ19: Unknown response: 0 0 0 0 0 0 0 0 0

#25 Post by dmq » 20 Dec 2017, 17:19

timbiker wrote:
18 Dec 2017, 10:05
But I though about that today, I recently wasted my time in having a lot of issue on a project. I just solved them in changing my power supply : as this sensor is quite hungry during peak, check with a good power supply and a good cable
Ah, timbiker. Cool. I just changed the power supply and now I have the same state as dgcracker, because I own the same B version. But it works.

Thanks TD-er and timbiker!

dmq
Normal user
Posts: 14
Joined: 09 Dec 2017, 19:15

Re: MH-Z19B - MHZ19: Unknown response: 0 0 0 0 0 0 0 0 0

#26 Post by dmq » 20 Dec 2017, 17:54

Just for information. The old power supply was rated at 5VDC/2A and the measurement was stable. The new one has the exact same values but works.

dmq
Normal user
Posts: 14
Joined: 09 Dec 2017, 19:15

Re: MH-Z19B - MHZ19: Unknown response: 0 0 0 0 0 0 0 0 0

#27 Post by dmq » 10 Jan 2018, 20:08

You seem to have the "B" version of the sensor, which gives a "0" as S-value.
Starting version dev-13, this will be supported, but you can also compile a version for yourself if you need it faster.
I don't think the new dev-13 release will take long, since the last 2 days, a lot of pull requests were merged and I think it is only testing for a (short) while with these new versions before the new release will be created.
Did already tested someone the dev-13 release and the "B" version? At the moment I have no access.

Thanks.

TD-er
Normal user
Posts: 838
Joined: 01 Sep 2017, 22:13
Location: the Netherlands
Contact:

Re: MH-Z19B - MHZ19: Unknown response: 0 0 0 0 0 0 0 0 0

#28 Post by TD-er » 12 Jan 2018, 15:40

dmq wrote:
10 Jan 2018, 20:08
You seem to have the "B" version of the sensor, which gives a "0" as S-value.
Starting version dev-13, this will be supported, but you can also compile a version for yourself if you need it faster.
I don't think the new dev-13 release will take long, since the last 2 days, a lot of pull requests were merged and I think it is only testing for a (short) while with these new versions before the new release will be created.
Did already tested someone the dev-13 release and the "B" version? At the moment I have no access.

Thanks.
Ehh I don't understand your post (maybe lack of coffee, or sleep, or both ;) )
Is your question about whether someone tested the latest builds? (both v2.0 and Mega have nightly builds now)
Or did you test it and it still doesn't work?

dmq
Normal user
Posts: 14
Joined: 09 Dec 2017, 19:15

Re: MH-Z19B - MHZ19: Unknown response: 0 0 0 0 0 0 0 0 0

#29 Post by dmq » 13 Jan 2018, 20:12

Ehh I don't understand your post (maybe lack of coffee, or sleep, or both ;) )
Nope, you were perfectly ok. I think I had too much coffee :roll:
Is your question about whether someone tested the latest builds? (both v2.0 and Mega have nightly builds now)
Yes, exactly. You wrote in another post:
You seem to have the "B" version of the sensor, which gives a "0" as S-value.
Starting version dev-13, this will be supported, but you can also compile a version for yourself if you need it faster.
Question is, if someone with this version of the sensor now can see the correct values in the interface and not only in the logs.

Thanks.

TD-er
Normal user
Posts: 838
Joined: 01 Sep 2017, 22:13
Location: the Netherlands
Contact:

Re: MH-Z19B - MHZ19: Unknown response: 0 0 0 0 0 0 0 0 0

#30 Post by TD-er » 13 Jan 2018, 23:31

With the latest builds, the B version of the sensor is fully supported.
I run one here for a while now.

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest