Output power from the generator is showing half of the actual wattage. I checked the terminals and found out that two current wires are going from the main breaker to the switchboard, c1, and c3. Using clamp meter, c3 is showing 0.80 amps while c1 is showing 0. I changed the terminal of c1 but no change in the amps. I also found leaked oil at this c1 terminal. I cleaned the oil and use conductor cleaner to clean the terminal but no change. It is a European style generator with output voltage 440V. One digital meter is showing 40kWatt but the analog meter is showing half power. The output voltage is correct 440V but the current is not right. The ammeter transfer switch shows zero current at line 1. line 2 and line 3 are OK. I also checked connectivity with a multimeter and it beeps which means the circuit is connected. I have been trying on this problem for many days but could not troubleshoot the real problem. Can anyone help me where the issue could be? I will really appreciate your help.

  • Hard to guess, more info about the generator and/or photos of what you,re looking at would be helpful. Also is this a Euro style 230V system or North American 120/240? – Harper - Reinstate Monica Oct 25 '18 at 20:51
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    Hello, and welcome to Stack Exchange. Measuring actual power is harder than just separately measuring voltage and current; you have to measure the product of the two. – Daniel Griscom Oct 25 '18 at 20:59
  • "One digital meter is showing 40kWatt but the analog meter is showing half power. " -- are the meters both measuring at the same point in the circuit? If so, why don't you think it's simply that one of the meters is not working properly? Your question is vague and lacking important details, which is probably why it's languished without garnering any really useful answers. If you're still monitoring this account, you should consider updating the question with the necessary information. – Peter Duniho Jan 8 '20 at 21:22

When your generator is running it will only provide the wattage that the load requires. If running at half the listed output of the generator add additional loads. If the problem is your generator voltage is drooping at 1/2 the load you may have problems with the exciter controll or poor or worn contacts could be the problem.


As told Voltage is 'fixed' by the generator but power depends on current drawn (Power = Current x Voltage x cos(Phi)) So watt-meter (resp. amp-meter) will measure just the power (resp. current) used by your load at that very time.

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