User manual

Publication 1760-UM001A-EN-P
Installation 2-5
Wiring Protection
Both AC and DC versions require wiring protection (F1) rated for at least 1 A
(slow).
When the unit is powered on for the first time, the power supply circuit draws a
larger surge current than usual. Use an appropriate device for switching on the
incoming power and do not use any reed relay contacts or proximity switches.
Using Surge
Suppressors
Inductive load devices, such as motor starters and solenoids, require the use of
some type of surge suppression to protect and extend the operating life of the
controller’s output contacts. Switching inductive loads without surge suppression
can significantly reduce the life expectancy of relay contacts. By adding a
suppression device directly across the coil of an inductive device, you prolong the
life of the output or relay contacts. You also reduce the effects of voltage transients
and electrical noise from radiating into adjacent systems.
The following diagram shows an output with a suppression device. We recommend
that you locate the suppression device as close as possible to the load device.
If the outputs are dc, we recommend that you use an 1N4004 diode for surge
suppression, as shown below.
Suitable surge suppression methods for inductive ac load devices include a varistor,
an RC network, or an Allen-Bradley surge suppressor, all shown below. These
components must be appropriately rated to suppress the switching transient
VAC/
Out 0
Out 1
Out 2
Out 3
Out 4
Out 5
Out 6
Out 7
COM
+dc or L1
Suppression
Device
dc COM or L2
ac or dc
Outputs
VAC/
Out 0
Out 1
Out 2
Out 3
Out 4
Out 5
Out 6
Out 7
COM
+24V dc
IN4004 Diode
Relay or Solid
State dc Outputs
24V dc common