Emco EE301-T, Manual

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b) Note down values at which R & L indications come. Let us say they come at 105V&
115V respectively.
c) Pass 1 Amp current through LDC and increase %R setting to 5%. Put polarity switches
in + position.
d) Vary the PT Voltage and note value at which R & L indications come. They should be
5.5V above set Values, i.e. R = 110.5V & L = 120.5.
e) Put VR switch to - position and vary voltage and check the voltages when R & L
indication come. They should be 5.5V below the set values i.e. R = 99.5 & L = 109.5.
Similarly check for 10% compensation. The difference will be +11V i.e. levels will be
L = 126V, R = 116V, for +VR & L = 104, R = 94V for -VR.
f) The %X Compensation cannot be checked, because of its small effect on AVR.
VERY IMPORTANT
1. Switch off CT current or short CT before disconnecting AVR.
2. When LDC is not to be used then both %X and %R dials should be kept at 0%. This
position will give 0 compensation.
B. AUXILIARY FAIL RELAY OPTION
AFR option can be incorporated in the same enclosure to give alarm instantaneously
when Auxiliary supply to the AVR Relay fails.
The internal relay remains energised as long as 110V A.C. (Aux supply) is present at
Pin Nos. 1 & 2 of the AVR relay. When Aux supply fails, this relay gets deenergised,
& the Contacts at pin No.7 & 8 close to operate the alarm (externally provided).
TESTING PROCEDURE
1) Give Aux supply 110V A.C. to the AVR Relay and check continuity between Pin Nos.
7 & 8. It should show open. Remove Aux supply to the relay and check the continuity
between Pin Nos. 7 & 8. It should show short.
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