Relay Output (Form C) - ero electronic ELK Manuel Utilisateur

2.8. Option 4
This is always a changeover relay output.
2.8.1.

Relay Output (Form C)

OP4
1
2
3
•
Isolated output 240Vac CATII
•
Contact rating: 2A 264Vac resistive
100mA 12Vdc minimum
•
Output functions: Heating, or cooling, or alarm.
18
* General Notes about Relays and Inductive
Loads
High voltage transients may occur when switching
inductive loads such as some contactors or solenoid
valves. Through the internal contacts, these transients
may introduce disturbances which could affect the
performance of the instrument.
For this type of load it is recommended that a
'snubber' is connected across the normally open
contact of the relay switching the load. The snubber
recommended consists of a series connected
resistor/capacitor (typically 15nF/100Ω). A snubber
will also prolong the life of the relay contacts.
WARNING
When the relay contact is open, or it is connected
to a high impedance load, it passes a current
(typically 0.6mA at 110Vac and 1.2mA at 240Vac).
You must ensure that this current will not hold on
low power electrical loads. If the load is of this
type the snubber should not be connected.
Part number HA028438. Issue 3.0. Oct-05