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Copyright 2006 TAC All Rights Reserved.
F-24853-4
Table-1 Software Assignments for Temperature Input.
INPNT = AI# (as shown below) /NOT
Wiring Length Error
The elements SCALE and OFSET are used to convert the
resistance reading to the proper engineering units. These
elements also provide a method of calibrating the sensor’s
displayed value to any desired value, thus correcting the
system for any errors that may result from wire length or other
variables.
Wiring length error can be eliminated by modifying the
element OFSET. Because the resistance of the wire will be
measured along with that of the sensor element, an error may
result.
AWG 24 wire has a resistance of 17 ohms per thousand feet.
If 50 feet of cable are used in a run, the resistance will be: 50’
x 2 (wires) x 17 ohms/1000’ = 1.7 ohms.
The sensor has a sensitivity of approximately 2.2 ohms per
degree. This 1.7-ohm error will result in a reading that is
approximately .77 higher than the sensor would read if the
wiring error were not present. To eliminate this error using the
element OFSET, simply subtract .77 from the value given in
the table for OFSET.
0-11 Vdc Analog Inputs
When configured as a voltage sensor input, the universal
analog input measures between 0 and 11 Vdc. The input
terminals provided for this range of voltage are terminals AI1-
AI8. Terminate the positive wire to terminal A and the negative
wire to terminal B. Terminal B is tied directly to ground on the
circuit board, so all voltages must be referenced to ground.
Differential and negative voltages must not be measured.
See Figure-5 below for wiring and setup information.
Figure-3 0-11 Volt Analog Input Wiring Information.
Option Slot # On The MSC-MPC Controller
AI#
1
2
3
4
AI1
AI 11
AI 21
AI 31
AI 41
AI2
AI 12
AI 22
AI 32
AI 42
AI3
AI 13
AI 23
AI 33
AI 43
AI4
AI 14
AI 24
AI 34
AI 44
AI5
AI 15
AI 25
AI 35
AI 45
AI6
AI 16
AI 26
AI 36
AI 46
AI7
AI 17
AI 27
AI 37
AI 47
AI8
AI 18
AI 28
AI 38
AI 48
SCALE
OFSET
CVTYP
1000 ohm Platinum RTD
Alpha = 0.00375
(American Alpha)
°F
346.4
-68.2
LIN L
°C
192.44
-55.67
LIN L
SCALE
OFSET
CVTYP
1000 ohm Platinum RTD
Alpha = 0.00385
(European Alpha)
TS-5800 Series
°F
337.4
-65.62
LIN L
°C
187.44
-54.23
LIN L
SCALE
OFSET
CVTYP
1000 ohm
Balco
TS-8000 Series
°F
312.81
-35.65
LIN 2
°C
173.78
-37.58
LIN 2
