Westermo Viper-008 - Manual (Page 10)

10 6641-2211
Fault Contact
The Viper switch is equipped with a potential free normally closed fault contact.
The fault contact is a solid state component (relay) that requires power to work and it
is transient protected. Additionally, the fault contact is opened when any of the following
conditions is met:
No voltage on the power supply pin, a voltage level outside the legal voltage range •
or current limitation on the voltage source is applied on the power input.
Description of how connection to the fault contact could be done is shown below.
The relay is closed when the unit is OK and open at failure. The relay is of semiconduc-
tor type (no moving parts). It is specified for max current 250 mA continuous,
500 mA peak (10 ms), operational voltage up to 110 V, protected by a 150 VDC-varistor,
ON-resistance less than 10 Ohm, and leakage current max 1 µA.
External relay
+24/48 VDC
+
1 kΩ
0V
Viper
2 2
4 4
Viper
To logic input
Input on PLC
Service port
The Service Port should not be used by non other than the Westermo Technical Support
team. Do not connect any device or cable to the Service Port.