110819-1317 EDT
daveinhomer:
When you get to the voltage display screen on the RDU what is displayed? 0, some strange value, or blank?
Your question has insufficient information to understand your problem. What does
"New unit installed, appears to be OK but does not read voltage" mean? What appears to work?
Then ", therefore dose not show usage.". What is usage? KWH or what? How does the voltage display have anything to do with whatever usage is? Note: that lack of display of voltage does not of necessity mean voltage is not used in the calculation of power.
Exactly what information can you display and what can you not display? Do the LEDs (MTU and RDU) both flash at about a 1 second rate?
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