SPX MARLEY LLC, User Manual

Page: 13 / 48

13
troubleshooting
The control panel has been tested before shipment and most issues lie outside
of the control panel e.g. proper probe connections to the control panel and
probe tip level heights in the basin of the cooling tower.
In an effort to troubleshoot the system please check the following:
• Check probe heights in the stilling chamber. The levels may be factory set
but if in question contact your Marley sales representative for level height
information. Probe wire height is secured using an adjustable cord grip
located inside the conduit box located on top of the stilling chamber.
• Check if probe wires are connected correctly at the user terminal strip lo-
cated inside the control panel. Each probe wire is printed with an identifying
number on the black insulation of the wire every few inches. For example
the reference probe is always #13 and needs to be connected to terminal
point #13 in the control panel.
• If probe wires are extended in the field, check to make sure the extension
wire is numbered correctly and connections are secure.
• After time, contaminates may build up on the probe tips. Clean tips with
an abrasive cleaning pad and make sure the tips are screwed in making a
good connection.
• If provided, the make-up selector switch on side of the control panel must
be in AUTO position
Checking the power circuit for the makeup solenoid
• Rotate the selector switch to the HAND position. The solenoid should ener-
gize allowing makeup water to flow into the cooling loop. Inside the control
panel is a single-pole circuit breaker which must be in the ON position to
power the circuit.
Checking control panel functionality
• To determine the control panel works as designed check the green LED
lights on each circuit card and watch the relays change state in the clear
cased relays located on each level card. Refer to the charts on pages 10
through 12 for LED light sequence of operation.
• Another method is to remove probe wiring from the terminal strip and simulate
water level by using jumper wires at the probe terminal points. For example
a jumper wire from #13 to #16 would indicate high-water alarm.