Nautel VS300, Preinstallation Manual

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VS300 Pre-installation Manual Planning for control and monitoring
Page 8-2 Issue 2.0 2010-12-01
External switching circuit requirements
The switching circuits for the remotely controlled functions must be the equivalent of a normally
open (momentary) switch. The switches must be configured to operate as a single-ended input using
the transmitter's 15 V dc as the source [see
“Option 1 - Single Ended Input (Internal dc supply)” on
page 8-2 ] or as a differential input using an external dc power supply (12 - 18 V) [see “Option 2 -
Differential Input (External dc supply)” on page 8-2 ] applied to A1J2A-9 and A1J2A-21.
Inputs are toggled between states by an active pulse unless otherwise noted. To ensure proper
operation, the duration of the active pulse should be a minimum of 250 ms. Refer to the
VS300
Operations and Maintenance Manual to see the various logic control options for digital inputs.
Option 1 - Single Ended Input (Internal dc supply).
When you use the transmitter's 15 V as
the source for a control function's opto-coupler, connect pins A1J2A-10 and A1J2A-22 to pins
A1J2A-9 and A1J2A-21 respectively.
Figure 8.1: Single-Ended Input Selected
When the digital input is configured for logic ‘0’, a negative logic (current-sink-to-ground) command
must be applied to the appropriate digital input (1 through 10). To avoid a ground loop, obtain the
ground from the
REMOTE I/O-A
connector A1J2A (pins 19 and 23).
Option 2 - Differential Input (External dc supply).
When you use an external dc voltage
(12 V to 18 V) as the source for a control function's opto-coupler, configure the control function's
external switching circuit for a differential input. Configure the
REMOTE I/O-A
connector for a
differential circuit by connecting the external dc supply to A15J2A pins 9 and 21.
CAUTION: When connecting an external supply, ensure that pins 10
and 22 of A1J2A are disconnected from pns 9 and 21 of A1J2A. Failure to
observe this may result in damage to the internal supply and exciter
circuitry.
GND
(+15 V INPUT)
EXCITER/
CONTROL
+15 V (internal)
PWB
S2110900 V2
CONFIGURED FOR INTERNAL DC SUPPLY
DIGITAL INPUT
J2A-9/21
J2A-10/22
J2A-19/23
REMOTE SELECTION CIRCUITRY