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Troubleshooting
Common Maker Test (Bench Power Supply)
D
Problem:
The Common Maker and thermostat are installed, the thermostat is receiving power,
and the ‘Equipment Will Not Start’ section did not resolve the issue.
This test will determine if there is a fault in the Common Maker. It can be tested either at the
equipment (page 5) or a bench power supply (page 6).
Testing at Bench Power Supply
Bench Power Supply
1. Set the multimeter to ‘Resistance’ (
Ω
) and connect it to the Receiver’s red and white wires.
If should read an ‘open loop’, typically displayed as ‘OL’ or ‘-1’.
2. Connect the Receiver’s black wire to one side of the 24V AC power supply.
3. Connect the Receiver’s purple wire to the Sender’s purple wire.
4. Connect the Sender’s white wire to the other side of the 24V AC power supply.
5. The relay in the Receiver should close, causing the multimeter to read between 0-1
Ω.
If the resistance is not less than 1
Ω
If the resistance is less than 1
Ω
but it doesn’t work when installed
•
The Common Maker is not working properly. It is covered by a lifetime
warranty that can be redeemed from the store it was purchased from, or
the manufacturer.
•
Check if the equipment requires an external power source (see diagram
‘E’ on the instructions). Some equipment may require a 24V transformer
to be connected to it in order to operate.
Purple
Black
Red
Purple
Black
(Disconnected)
White
White
Bench Power Supply
Multimeter
24V AC Power
Receiver
Common
Maker
00.1
ȍ
V~
V
A
DIGITAL
MULTIMETER
Sender
