DCA
Page 8
Setup for the PC DCA.
There are two methods of
carrying out the calibration setup connections on the
PC DCA. Most often the unit is installed in one of
Moore Industries’ card racks, and the calibration
equipment is connected to the appropriate rack
terminal strip.
Figure 5 illustrates the PC DCA installed in the
surface mounted card rack, the SMR. Figure 6 shows
the terminal strip labeling for rack units when the DCA
is equipped with the DI Option.
As an alternative to using the card rack, individual PC
DCA’s can be checked with Moore Industries’ Pro-
cess Power Supply, the PPS, equipped with its CT
Option. The CT-equipped PPS accepts the connec-
tion strip of the PC DCA in a connector built into its
side panel. The PPS front panel provides access to
terminal strips similar to those used on the card
racks.
Whether using the card rack or the PPS/CT combina-
tion, note that the DC power connections are not
made directly to the unit, but to the terminal strips of
either the card rack or the PPS. DC power is supplied
to the DCA at its pins 8 and 9
NOTE
The “UPPER” and “LOWER” labeling used
on the DCA is for reference purposes only.
The trip point pots allow for adjustments through 100-
percent of span. It is therefore possible for the
connections to the “LOWER” labeled alarm section to
be configured as a “high alarm”, and the “UPPER”
section to be configured as a “low alarm”.
NOTE
The LED’s DO NOT always indicate an
alarm condition; rather, they light to show
that their complimentary relay is ener-
gized. It is possible for a DCA to be
configured such that the LED’s are lit
when input is in a “non-alarm” state.
Figure 4.
STD DCA with DI Option Terminal Locations
LNO —
LOWER RELAY NORMALLY OPEN
LNC —
LOWER RELAY NORMALLY CLOSED
+IN LOW — LOWER
CURRENT/VINPUT
-IN — NEGATIVE INPUT
+IN UP — UPPER
CURRENT/VINPUT
COM — COMMON
ACC — –DC
AC — +DC
GND
