Maker Pro
Maker Pro

Modified wiring, your thoughts?

paulmars

Aug 30, 2016
19
Joined
Aug 30, 2016
Messages
19
Id like to move the red wire for the kwh meter shown from before to after the coil. Your thoughts?
 

Attachments

  • Screenshot_20230803-084047.png
    Screenshot_20230803-084047.png
    304.6 KB · Views: 14

Bluejets

Oct 5, 2014
6,990
Joined
Oct 5, 2014
Messages
6,990
Why..??
It's a potential line, would make no difference what-so-ever.
 

paulmars

Aug 30, 2016
19
Joined
Aug 30, 2016
Messages
19
I think it would change what the meter monitors, which is fine by me, as long as I'm not missing something that might cause an issue
 

Bluejets

Oct 5, 2014
6,990
Joined
Oct 5, 2014
Messages
6,990
I think it would change what the meter monitors,
No, it won't change anything.
As I said above, the red lead is a potential lead.
Meter monitors the current in the CT, that's it.

as long as I'm not missing something that might cause an issue
There may be local authority issues if it was wired as in your photo (yuk ) and it was part of a local authority monitored system, but other than that , no change to the way it works.

Just a word of caution with ct's.
NEVER allow the CT to be open circuit as extremely high (lethal) voltages can be generated.
If disconnecting from the monitor device, have power off and short out CT secondary if it is left with the primary in circuit.
 

paulmars

Aug 30, 2016
19
Joined
Aug 30, 2016
Messages
19
That is wiring diagram came with meter. Every meter that i looked at was wired like that. I think the "output' label is incorrect. Those wires go to the load, as the diagram below shows.

It would b easier since im dealing with 8 awg wire to join the meter wire to the 8 awg on other side of coil.
 

paulmars

Aug 30, 2016
19
Joined
Aug 30, 2016
Messages
19
Slightly more current will be going thru the coil with my modified wiring.
 

kellys_eye

Jun 25, 2010
6,514
Joined
Jun 25, 2010
Messages
6,514
The difference is entirely the total current drawn by the metering device - that's it. If the meter is actually reading more than 10A in normal operation then the 'difference' is going to be less than the meters actual accuracy - in other words, negligible.
 

paulmars

Aug 30, 2016
19
Joined
Aug 30, 2016
Messages
19
I agree with your 1st statement, but fail to understand your second.
 

kellys_eye

Jun 25, 2010
6,514
Joined
Jun 25, 2010
Messages
6,514
I agree with your 1st statement, but fail to understand your second.
That meter is set to measure up to 100A therefore it's accuracy (say 1%) would be +/- 1A (fsd). If the meter itself only draws 100mA (and it's probably a lot less) than this additional load is under the accuracy range (one TENTH of the permissible error reading) and therefore can be ignored as a load - in other words it won't matter where you connect the meter, before or after the pickup coil.

Does the display even show to a decimal position? If it shows ONE decimal position you 'might' notice the meter current draw but, still, the meter itself isn't that accurate.
 

kellys_eye

Jun 25, 2010
6,514
Joined
Jun 25, 2010
Messages
6,514
You should have insulation over the bare earth wire otherwise it looks ok to me.
 

paulmars

Aug 30, 2016
19
Joined
Aug 30, 2016
Messages
19
1-why?
2-Im concerned about the meter power wires; one is labeled neutral. I know that means nothing,but still it concerns me. Why would they label that differently then the load wires?
3-any idea what that thin black wire going up and out of the picture is?
 

kellys_eye

Jun 25, 2010
6,514
Joined
Jun 25, 2010
Messages
6,514
1. You have exposed live terminals nearby and 'bending' of the earth wire could allow it to touch - BANG!
2. The supply for the meter is generated by a capacitor dropper circuit and this, if connected in reverse, will still work but can leave other parts at full mains potential. Observe any polarities any time they are marked as such.
3. Potentially a thermal sensor input. What's on the other end?
 
Top