Teseq NSG 3040, Руководство пользователя

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NSG 3040 EMC test system
9 DESCRIPTION OF THE 25 PIN D-SUB
SIGNALS
9.1 Interlock
Between Pin 5 (hi) and Pin 2, 8, 15, 20 (low).
This connection is an integral part of the interlock safety circuit. If a number
of units are incorporated in a system, then these connections can be “daisy-
chained” together to form a single safety circuit. If no external interlock circuit
is required then the shorting connection must be made by using the terminator
connector supplied. Otherwise pulse generation in the system will be inhibited.
A built in circuit breaker enables the EUT power supply also to be switched off,
while the interlock function only blocks the generation of pulses or any other
ongoing test resp.
The interlock is a safety function to ensures the following:
The interlock forms a bus to which all instruments in a system are con-
nected.
Good EMC engineering practises should be applied
when connecting signals to this port. As the whole
system generates disturbances, in order to avoid auto
disturbing, all wires connected to this port should be
properly shielded, the shield of the cable not serving
as signal return path, the shield to be connected via a
large surface to the conductive shell of the Sub-D plug.