Honeywell UDC2500 - Manual (Page 82)

Configuration
68 UDC2500 Universal Digital Controller Product Manual 4/07
Function Prompt
Lower Display
Selection or Range of Setting
Upper Display
English Numeric
Code
English Numeric
Code
Parameter
Definition
DEV 4 DEVIATION (PROCESS VARIABLE
MINUS SETPOINT)—Represents –100 %
to +100 % of the selected PV span in
engineering units.
Zero deviation will produce a center scale
(12 mA or 50 %) output. A negative deviation
equal in magnitude to the Auxiliary Output
High Scaling Factor will produce a low end
output (4 mA or 0 %) output. A positive
deviation equal in magnitude to the Auxiliary
Output Low Scaling Factor will produce a
high end output (20 mA or 100 %).
FOR EXAMPLE:
Input 1 = Type T High Thermocouple
PV range = –300 °F to +700 °F
PV span = 1000 °F
Deviation Range = –1000 °F to +1000 °F
Auxiliary Output Low Scale Value = 0.0
Auxiliary Output High Scale Value = 1000
If PV = 500 °F and SP = 650 °F
then Deviation Display = –150 °F, which
is
–7.5% of the Deviation Range, so
Auxiliary Output = 50% – 7.5% = 42.5%
OUT 5 OUTPUT—Represents the displayed
controller output in percent (%). Cannot be
used with
Three Position Step Control.
SP 6 SETPOINT—Represents the value of the
setpoint currently in use and is shown in the
same units as those used by the PV.
LSP 1 7 LOCAL SETPOINT ONE—Auxiliary output
represents Local Setpoint 1 regardless of
active setpoint.
LSP 2 8 LOCAL SETPOINT TWO—Auxiliary output
represents Local Setpoint 2 regardless of
active setpoint.
0PCT 902 Value in
Engineering Units
AUXILIARY OUTPUT LOW SCALING
FACTOR— This is a value in engineering
units used to represent all AUX OUT
parameters except Output.
For Output, this is a value in percent and can
be any value between –5 % and +105 %.
However, keep in mind that relay output
types can only be scaled 0 % to 100 %.