Harris Institute of Technical Training

I have a 240 volt 3 wire 3 phase form 12s meter on a three wire 240 volt service ungrounded for three phase load only. However, the customer is using one leg for lighting and causing the meter to go backwards. Is there a way for the customer to have single phase load by using drypack transformer and still meter correctly.

Meter Tech Frank
[This question was posted on a similar question from March 2013, but we just came across this and wanted to bring it up higher to awareness or questions for others to see].

Meter Tech Frank,
What I can derive from your question is that the customer is using one leg, but they must have another voltage that they are using this with to connect the lighting load. This metering problem can be resolved with a drypack transformer that is connected across any of the 240v voltages from the 3 wire system. The 12S meter will correctly meter the 3 phase 3 wire load and will also correctly meter any phase to phase connected load. So, that is my suggestion. Have them use a drypack transformer connected phase to phase to remedy this problem. If you have any further questions, give me a call or post here.
Brad