Testing The Relay Circuits - Ametek Drexelbrook Z-tron Level Control 502-302X Series Installation And Operating Instructions Manual

502-302 Series Z-tron Level Control
X
5.4 Testing the
Relay Circuits
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Use the following steps to check out the relay circuits:
a. The relay circuits consist of double-pole double-throw
relay contacts brought out to terminal strips. When
the relays are operating properly, two pairs of contacts
will be open with high or low level, and two pairs will
be closed with high or low level. See Figure 5-4.
LOW LEVEL FAIL SAFE
LEVEL BELOW
IS OUTALARM LED
GND 7 8 9
TRIP POINT
L1 L2 3 4 5
LEVEL ABOVE
GND 7 8 9
TRIP POINT
L1 L2 3 4 5
b. Relay operation may generally be heard as an audible
click when the background noise is not too high. Use
one of the methods shown in Figure 5-5 to determine if
the relay contacts are switching.
d. Difficulty in calibration can often be traced to improper
wiring of the relay terminals to an annunciator or
other panel device. Check the wiring against the relay
chart in Figure 5-4.
26
HIGH LEVEL FAIL SAFE
ALARM LED
LEVEL BELOW
TRIP POINT
IS OUT
L1
ALARM LED
LEVEL ABOVE
IS LIT
TRIP POINT
L1
Figure 5-4
Relay Circuit Operation
Figure 5-5
Relay Circuit Wiring
Troubleshooting
ALARM LED
GND 7 8 9 IS LIT
L2 3 4 5
GND 7 8 9
ALARM LED
IS OUT
L2 3 4 5