Phase sequence detector Problem

Hi friends,
few days back i got the below given "Phase sequence detector" from this forum & i tried it. It worked very well. But when i used this circuit in parallel with my 3 phase voltmeter it gave problem. Probelm:- when one of the 3 phases isn't present i.e one phase is open i get voltage in that phase back, rougly around 108 Volts. Ideally it should be 0. I'm unable to find out the reason. I tried inserting some diodes in Phase sequence detector circuit, but no use. Can someone please help me .

Thanks.

That's caused be leakage current from the other phases being conducted through the diodes and resistors in the circuit.

Try connecting small (about 5W) filament lamps between each phase and neutral and it should solve the probelm, if you don't have any lamps you could try resistors, try 22k 3W carbon film.

thanks a lot..i tried using 22k 2w resistor 33w wasnt available....now it shows 5 volts...but the resistors get heated up like anything...wht to do to prevent heating up of these resistors i think 5w will also be not sufficient..i cant use bulbs...

What's the nominal voltage of the three phase?

You could try 100nF to 1:mu:F capcitors with 1M bleader resistors in parallel; make sure the capacitors have a high enough voltage rating though.

Failing that, try replacing the 100k resistors in this circuit with 1M resistors and adding 100k resistors from each phase to neutral.

It might help to connect the common line of your phase detector to neutral (in addition to changing the input resistors to 1M).

Thank is a good circuit i need that