SocomecDIRIS A40

[Ozzie010]

Hi Guys,

We have some Socomec DIRIS A40 panel mount meters installed on a job 200 to be precise.

We are getting negative readings from nearly all of the meters.

Some of these readings are very low while some are nearly the same as the Positive reading. Current Transformers have been checked and are wired correctly, Also the meter an Auto-Correct function which can invert CT's if required and has been checked and is showing no indication of reversed CT's on the meters.

My understanding is ( Open to correction here )

Positive Power + is the energy that is being Imported and consumed by the installation.

Negative Power - is the energy that is being Exported from the installation for instance like solar panels ect. (Which we dont have)

When speaking with the Socomec agents they say that this is normal behaviour for the meter. However from speaking with every other person I meet is of the same opinion I am.



Any thoughts on this would be greatly appreciated,

Kind Regards,
Ozzie010

 

[Socomecagent]

Hi,

You are right, regarding the IEC standard :
- if the energy (or the power) is positive, the load is in consumption (energy is going from the utility to the load)
- if the energy is negative (or the power), the load generates power (energy is going from the load to the utility)

For me it's more a cabeling issue. Con you give us :
- the current
- the voltage
- the PF
- P, Q and S

With theses informations we could detect where is the problem.

Regards

 

[Ozzie010]

Hi SocomecAgent thanks for your reply,

Attached is some sample data sample data from one meter

http://files.engineering.com/getfil...ae-4ca3-924b-3c625e43f789&file=Test_Meter.png

What is strange about the results which have been the same on 4 meters is that when the installation is under no load the meter reads a negative kW reading. My theory is that this value is accumulating over time leading to the negative kW's but Why??. There is more negative kW been generated than positive kW on this meter but when tested it indicates that everything is ok

Also when the installation was ran under load for this period there was no negative kW generated which indicate that CT wiring is OK.


Regards

 

[Ozzie010]

Any other thoughts on this

 

[Socomecagent]

Hello,

These values a completely normal because of the load. Under 20% of load we cannot guarantee any accuracy.
As example, when you look at the standard of the current transformer, for a 0,5 CT , the CEI says : class 0,5% is ok from 100% to 120% of the norminal current and accuracy is deacresing to 1,5% at 20% of load. Below, no specific requierment for the load.
After, this current is used by the product, which caluclates P, Q F PF (etc..), and add also an accuracy error.

So when you have no load, values are not significant.

Regards

 

[Ozzie010]

Thanks