GE Energy
D20/D200
Installation and Operations Guide
General 994-0078-2.00-7
Full
31
Familiarization
, continued
D20C
Combination
I/O Peripheral
The D20C is a combination I/O module that is used for small-point-count
applications. The D20C can be configured with:
•
16 digital inputs
•
8 momentary or dual function trip/close control outputs
•
16 analog inputs
•
8 analog inputs and 8 analog outputs.
The D20C performs all the I/O processes similar to the other D20 I/O modules, but
uses a faster clock speed to meet the increased processing power demand.
Interposing relays may be supplied using a WESTERM D20KI, as with the D20K.
A Local/Remote switch is provided to turn off relay coil power, and put the module
off-line. An on/off-line indication is sent to the D20/D200, which is available to the
host as a pseudo-status.
D20C Daughter
Boards
D20C1 and D20C2 daughter boards are available as options for the D20C peripheral.
They are mounted on the D20C WESDAC to give additional analog inputs and
analog outputs, as shown below:
Table: D20C
Options
WESDAC Board
Digital
Inputs
Digital
Outputs
Analog
Inputs
Analog
Outputs
D20C
16 8
D20C with D20C1 Daughter Board
16
8
16
D20C with D20C2 Daughter Board
16
8
8
8
D20AC Analog
Input
Peripheral
The D20AC peripheral, which is the alternating current analog input module for the
D20 product line, provides:
•
Up to six 50/60Hz voltage inputs
•
Up to nine 50/60Hz current inputs
•
One DC input
To provide isolation, the termination panel uses current and potential transformers on
the AC inputs, and an isolation transformer on the DC input. The current inputs
utilize a compressor to achieve an eight-times reduction of the input signal. The AC
current and voltage inputs, and the DC input are buffered before being multiplexed
into the analog-to-digital (A/D) converter section.
