Advantech iDAQ-731, User Manual

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iDAQ-731_751_763D User Manual 14
2.2.5 Solid-state Relay (SSR) Output Connection
A solid-state relay (SSR) output channel sends a signal to control the ON/OFF state
of an SSR. The state of the SSR then decides if the load is conducting or not. This is
shown in Figure 2.9.
Figure 2.9 Solid-state relay output signal connection.
The SSR is non-directional. The load voltage polarity can be either direction. Both the
voltage of the external voltage source and the load current must be within the range
as specified in A5. Solid-State Relay (SSR) Output. The device may be damaged if
the voltage or current is beyond the maximum value.
The SSR provides galvanic isolation protection, which can withstand a large continu
-
ous voltage between external side and internal side. This prevents device damage
when such fault condition happens.
The device is also equipped with a transient voltage suppressor for each channel.
When the relay which is connected to an inductive load becomes OFF, a large back
EMF will be generated. The suppressor clamps the EMF to a maximum value which
does not damage the device.