APC Modular Remote Power Panel (PDPM277H) kW indication

[DCIM_Support]

Hello!

Can someone answer me, please, why such difference in APC Modular Remote Power Panel (PDPM277H) kW indication appears:

5.30 kW > 5.0 kW and 5.90 kW > 5.5 kW. So the difference of those two indications are respectively 0.3 kW and 0.4 kW. I thought the "System Output Total Power" should be equal to sum of "Module Output Power".

Best regards,

Janis Magazeinis

(CID:118001986)

[DCIM_Support · Accepted solution]

Hi Janis,

Assuming the values that are being summed are coming directly from the device and assuming that the "System Output Total Power" is coming from the device as well, it would appear to be a device accuracy issue.

Can you verify the output of the device? I'm assuming this is a modbus device so polling this from a gateway or 3rd party system should be able to tell you if the numbers shown for the modules are accurate or if the DDF is rounding the numbers. If it is SNMP, the same can be done with a 3rd party SNMP utility.

If when polling the device externally the numbers show up as 0.7 , 0.8, and 0.4 or even 7, 8, and 4. then the device is likely limiting the accuracy itself. If it is showing as something more like 72, 85, and 44, then it would appear to be the DDF rounding down. 

The DDF team may have a better idea if the DDF itself is set up that way and hopefully they'll take a look at this too.

Thanks,

Steve

(CID:118002002)

[DCIM_Support]

Hi Steven Marchetti and Janis Magazeinis,

I can supplement the question of Janis Magazeinis with the details that Steven Marchetti asks, i.e.:

Can you verify the output of the device? ...

Since I have to use a certain amount of PDPM277H and every year during the next visit of Schneider Electric service personnel, I ask them the same question very similar to the question Janis Magazeinis.

For clarity, I divided the SNMP output into several parts. All parts, i.e. SNMP requests were made for the same PDPM277H device for all inserted modules and at the same time (about 3...5sec).

textPDPM277H Total System OutputsSystem Output Voltage Phase to Neutral - /10V: SNMPv2-SMI::enterprises.318.1.1.22.4.1.15.1.3.1 = INTEGER: 2279 SNMPv2-SMI::enterprises.318.1.1.22.4.1.15.1.3.2 = INTEGER: 2282 SNMPv2-SMI::enterprises.318.1.1.22.4.1.15.1.3.3 = INTEGER: 2283 System Output Voltage Phase to Phase - /10V: SNMPv2-SMI::enterprises.318.1.1.22.4.1.15.1.4.1 = INTEGER: 3937 SNMPv2-SMI::enterprises.318.1.1.22.4.1.15.1.4.2 = INTEGER: 3937 SNMPv2-SMI::enterprises.318.1.1.22.4.1.15.1.4.3 = INTEGER: 3937 System Output Current per Phases - /10A: SNMPv2-SMI::enterprises.318.1.1.22.4.2.11.1.3.1 = INTEGER: 121 SNMPv2-SMI::enterprises.318.1.1.22.4.2.11.1.3.2 = INTEGER: 222 SNMPv2-SMI::enterprises.318.1.1.22.4.2.11.1.3.3 = INTEGER: 141 System Output Power per Phases - /10kW: SNMPv2-SMI::enterprises.318.1.1.22.4.3.5.1.2.1 = INTEGER: 26 SNMPv2-SMI::enterprises.318.1.1.22.4.3.5.1.2.2 = INTEGER: 47 SNMPv2-SMI::enterprises.318.1.1.22.4.3.5.1.2.3 = INTEGER: 30 Total System Output Power - /10kW: SNMPv2-SMI::enterprises.318.1.1.22.4.3.1.0 = INTEGER: 104textPDPM277H Breakers Output Current per Phases and per ModulesBreakers Output Current per Phases and per Modules - /10A: SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.1.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.1.2 = INTEGER: 6 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.1.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.2.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.2.2 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.2.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.3.1 = INTEGER: 5 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.3.2 = INTEGER: 20 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.3.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.4.1 = INTEGER: 18 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.4.2 = INTEGER: 18 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.4.3 = INTEGER: 17 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.5.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.5.2 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.5.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.6.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.6.2 = INTEGER: 8 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.6.3 = INTEGER: 14 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.9.1 = INTEGER: 13 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.9.2 = INTEGER: 39 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.9.3 = INTEGER: 14 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.10.1 = INTEGER: 6 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.10.2 = INTEGER: 6 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.10.3 = INTEGER: 45 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.11.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.11.2 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.11.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.12.1 = INTEGER: 26 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.12.2 = INTEGER: 19 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.12.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.13.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.13.2 = INTEGER: 12 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.13.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.14.1 = INTEGER: 21 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.14.2 = INTEGER: 32 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.14.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.15.1 = INTEGER: 24 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.15.2 = INTEGER: 36 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.15.3 = INTEGER: 21 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.16.1 = INTEGER: 8 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.16.2 = INTEGER: 29 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.9.16.3 = INTEGER: 30textPDPM277H Breakers Output Power per Phases and per ModulesBreakers Output Power per Phases and per Modules - /10kW: SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.1.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.1.2 = INTEGER: 1 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.1.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.2.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.2.2 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.2.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.3.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.3.2 = INTEGER: 3 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.3.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.4.1 = INTEGER: 3 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.4.2 = INTEGER: 3 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.4.3 = INTEGER: 3 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.5.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.5.2 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.5.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.6.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.6.2 = INTEGER: 1 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.6.3 = INTEGER: 3 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.9.1 = INTEGER: 2 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.9.2 = INTEGER: 8 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.9.3 = INTEGER: 2 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.10.1 = INTEGER: 1 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.10.2 = INTEGER: 1 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.10.3 = INTEGER: 9 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.11.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.11.2 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.11.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.12.1 = INTEGER: 5 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.12.2 = INTEGER: 4 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.12.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.13.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.13.2 = INTEGER: 2 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.13.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.14.1 = INTEGER: 4 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.14.2 = INTEGER: 6 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.14.3 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.15.1 = INTEGER: 4 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.15.2 = INTEGER: 7 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.15.3 = INTEGER: 4 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.16.1 = INTEGER: 1 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.16.2 = INTEGER: 6 SNMPv2-SMI::enterprises.318.1.1.22.2.4.1.11.16.3 = INTEGER: 6textPDPM277H Modules Output Power (3ph mod - summ, 1-ph mod - per lines)Modules Output Power (3ph mod - summ, 1-ph mod - per lines) - /10kW: SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.1.1 = INTEGER: 1 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.2.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.3.1 = INTEGER: 5 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.4.1 = INTEGER: 11 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.5.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.6.1 = INTEGER: 5 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.9.1 = INTEGER: 2 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.9.2 = INTEGER: 8 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.9.3 = INTEGER: 2 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.10.1 = INTEGER: 1 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.10.2 = INTEGER: 1 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.10.3 = INTEGER: 10 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.11.1 = INTEGER: 0 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.12.1 = INTEGER: 9 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.13.1 = INTEGER: 2 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.14.1 = INTEGER: 11 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.15.1 = INTEGER: 16 SNMPv2-SMI::enterprises.318.1.1.22.2.6.1.20.16.1 = INTEGER: 14

Thus, by following some simple math, you can see a lot of "inconsistencies".

For example, for a three-phase module number 16, assuming that we have a purely active load (power factor = 1), the total real power should be:

227.9V*0.8A+228.2V*2.9A+228.3V*3.0A=0.18232kW+0.66178kW+0.6849kW=1.529kW

And instead we have according to SNMP output for module number 16:

0.1kW, 0.6kW and 0.6kW respectively (summ 1.3kW) and total power 1.4kW

And such rounding inside the device can be found pretty much from the level of a separate breaker, and ending with the level of the entire device as a whole.

Thus, you can verify, that the above inaccuracy does not apply to either the DCE-server or its DDF-files, but only to the PDPM277H device. I.e., as people usually say in such cases: "working as designed" 😀.

With respect.

(CID:118002982)

[DCIM_Support]

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