Hardware Support - CM4000 Power Meter

[jonathanzamban]

We have 8no. CM4000 power meters installed onsite.

They are daisy-chained over RS-485 (4-wire) to an EGX150 unit (all within the same panel).

Some of these units simply stopped responding to the EGX's polling request (the Tx and Rx LEDs stopped blinking).

Upon power reboot of the units, the meter seems to be receiving the requests (Rx LED blinking), but not transmitting any data (Tx LED not blinking).

Any idea what can have caused this with the meters?

We tried to replace the EGX, but no success.

We also tried to connect only 1no. CM4000 individually to the EGX, but no success.

Unfortunately I could not find anything in the CM4000 manual about it.

We first thought that it could be an issue with the CM4000's comms card, but it would be unlikely that three of them would have the same issue, all at the same time.

Thanks in advance for your help,

Jonathan.

[Charles_Murison]

Hello @jonathanzamban ,

Hard to say root cause from description and video alone. First question is if any settings on the meters have changed. If you connect directly to meter can the meter respond?

Regards,

Charles

[jonathanzamban]

Hi Charles,

We have not changed any settings or parameters on any of the meters.

If we attempt to connect directly to it, it does not respond.

We had the same issue with a similar meter in a different serial chain.

We first thought that the communication card was faulty (as the Tx was not blinking upon requests), so we had the technicians onsite to replace the meter with a PM8240 (changing to an ethernet layout). They stripped all the cables from the CM4000, but could not change the CTs at the time, so they put the meter back to continue another time... and the meter started working again (?!). No issues with that unit ever since.

We tried to strip all the cables from the CM4000 that is not working at the moment, in case the situation would repeat itself - but not so lucky this time around.

That is why this time I decided to ask the question here, if it has ever been seen this behavior with the Rx/Tx LEDs.

Thanks for your help so far,

Jonathan.

[Charles_Murison · Accepted solution]

Hello @jonathanzamban ,

Recommend you reach out to your local technical support to troubleshoot if you need further help.

Regards,

Charles