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If using two outputs in a heat/cool type control, please refer to Appen-
dix D for more details.
Relay
• Connecting a load to full capacity of the relay will shorten the relay
life, especially if it is operated at a rapid rate. To protect the output
relay, an external relay or a contactor should be used. If a higher
current rating is required, a solid-state relay driver type output is
recommended.
• Connect the load between the normally opened contacts of the relay.
This way, if power to the controller is disrupted, the output circuit
would open, preventing the load from running out of control.
• Set the proportional time cycle parameter, “TC” to 15 secs. or more
(30 secs. typical).
• Use of MOV circuit is recommended to
protect the relay against switching
surges and to ensure the product’s long
life. Connect it between the contacts of
the relay as shown in the example.
Part No.:
MOV-100
(power supply voltage: 100V)
MOV-200
(power supply voltage: 200V)
DC SSR Driver (voltage pulse)
• The non-isolated DC output is used to drive an external load-handling
device such as Solid-State Relay(SSR) or Solid-State Contactor(SSC).
• The total current drawn, for both single and dual outputs, should be
within the allowed value.
• Make sure the polarity is correct.
• Set the proportional time cycle parameter, “TC” to 1 sec. or more.
6 5 4 3
5
6
7
8
9
CN4420
(8-pin)
CN4620