Harris Atlas DVL400, Technical Manual

Page: 113 / 180

2/25/03 888-2473-001 4-13
WARNING: Disconnect primary power prior to servicing.
Section 4 Theory of Operation
ATLAS Series™
4.3.6.1 External Interlocks
There are 4 External Interlock terminals provided on J18 which will shut the
transmitter off when the circuit is opened. These are primarily to be used for the
protection of personnel. The External Interlock circuit requires a closed contact
between J18-1 and ground. This activates the External interlock relay K1 and allows
the transmitter to turn on. J18 is designed to allow connection of up to 6 serially
connected external interlock contacts. The transmitter is shipped with 6 jumpers
installed on J18, bypassing all of the external interlocks. The jumpers are installed
as follows:
•
J18-1 to J18-2 - Interlock #1
•
J18-3 to J18-4 - Interlock #2
•
J18-5 to J18-6 - Interlock #3
•
J18-7 to J18-8 - Interlock #4
To use any one of the interlocks simply remove a jumper and connect the terminals
to the interlock contacts of the external device. If the device opens the contact, the
transmitter will be shut off. If the external interlock is not going to be used, all 6
jumpers must be installed, effectively connecting J18-1 to ground to allow the
transmitter to turn on.
The External Interlock circuit uses relay K1 to directly drive the parallel control
lines on the System Control Bus. If an interlock circuit is opened, relay K1 will
relax to the position shown on the schematic. This will apply an RF Mute, PS Mute
and most importantly Fault OFF. The transmitter is now shut off and cannot be
turned on again until the external interlock circuit is closed and a new ON command
is given locally or by remote.