Harris DX 25U, Техническое руководство

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P.7
Interlock Status Logic: Circuit De-
scription
Interlock Status logic is shown on Sheet 1 of the Controller
schematic diagram.
Figure P-7 is a simplified diagram of
Interlock Status Logic.
The Interlock circuits and Interlock Relay K3 are shown on the
Transmitter Overall Schematic Diagram, Sheet 2. Part of the +30
Vdc “Interlock Status” circuit appears on the DC Regulator Sche-
matic Diagram. A simplified diagram of the interlock circuits (but
not interlock logic) is in SECTION M, DC Regulator.
P.7.1
Interlock Status Logic: Inputs
Refer to Interlock Status Logic: Simplified Diagram, Figure
P-7, in this section. There are three inputs to the Interlock status
logic on the Controller:
a. Door Interlock (Logic HIGH if “Fault”)
b. External Interlock (Logic HIGH if “Fault”)
c. Interlock String (Logic LOW if “Fault”)
P.7.1.1 Door Interlock Input
Door interlocks include the Driver Compartment inner access door,
the Center Control Compartment RF Amp inner access door and
the Left Control Compartment RF Amp inner access door.
When all doors are closed, the door interlock switches ground
the “Door Interlock” input to Q9-2. If one or more doors are
open, +30 Vdc is applied to the “Door Interlock” input on the
Controller, through a resistor on the DC Regulator.
The “Interlock String” circuit applies a logic HIGH from the +30 Vdc
supply for the interlock “fault” inputs.
P.7.1.2
External Interlock Input
External interlocks include enclosures with rf power inside,
such as phasor cabinets; air or water flow interlocks on dummy
loads; interlocks on rf power contactors; and any other external
interlocks which may be required by your system.
The “External Interlock” at External Interface TB1-1 and 2, is
a 24 Vac circuit. A closed circuit must be provided between these
terminals to energize interlock relay K3. When K3 is energized,
the “External Interlock” input to the Controller is grounded
through a contact on K3. If the circuit between TB1-1 and 2
opens, relay K3 de-energizes, and a logic HIGH is applied to
the “External Interlock” input on the Controller from the +30
Vdc supply through a resistor on the DC Regulator.
P.7.1.3
Interlock String Input
The Interlock String protects against the loss of interlock sens-
ing. The loss of +30 Vdc disables the Door and External inter-
Figure P-5. Tri-State Buffers (817 1280 094)
Figure P-6. Multiplex & Latch, Simplified Diagram
817 1280 095
DX-25U
P-14 888-2297-002 Rev. S: 05-02-97
WARNING: Disconnect primary power prior to servicing.