RE-TRANSMITTED ANALOG OUTPUT (Optional)
The re-transmitted analog output option transmits a digitally programmable 4
to 20 mA or 0 to 10 VDC signal to drive chart recorders, remote indicators and
controllers. The option is contained on the upper PCB and has two outputs,
“ANALOG-” (TBB #10)
and
“” (TBB #11)
and is self-powered
(active)
with a compliance of 10 VDC. The analog “-” output is isolated from the
input common, eliminating problems from ground loops. Programming of the
option is performed in
“Pro 8” of the normal programming mode. Display
values are simply keyed in to provide a 4 mA or 0 VDC output, “AN-Lo”
, and a 20
mA or 10 VDC output,
“AN-HI”
. The analog output then follows the assigned
value and as such will update every measurement cycle. Nonstandard current or
voltage ranges can be supported by calculating the slope and intercept of the
display/output and calculating the required display values at 4 mA (0 VDC) and
20 mA (10 VDC). Reverse action can be achieved by programming a
“high”
display value for
“AN-Lo”
and a
“low”
display value for
“AN-HI”
.
If the display should indicate an
“OPEN”
or
“SHort”
the analog output will
go to 20 mA (10 VDC) for an open and 4 mA (0 VDC) for a short.
Note: Analog “-” must be kept isolated from Alarm Comm. (TBB #8).
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ANALOG OUTPUT DIAGRAMS