Carrier TruVu TV-MPCXP1628-NR, Руководство по установке и запуску

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To adjust input and output properties
TruVu™ MPC Controller ( part no. TV-MPCXP1628-NR) CARRIER CORPORATION ©2021
Installation and Start-up Guide All rights reserved
43
Offset/Polarity values
Offset/Polarity is not particular to a type of input or output, but the driver handles analog and binary inputs and
outputs differently. To set these values appropriately, you should understand how the driver uses them.
Offset/Polarity Notes
Analog Input (BAI) Offset value (positive or negative) adds a fine adjustment to a sensor reading after all
scaling for calibration.
EXAMPLE If a sensor reads 74.9°F when the actual measured value is 73.6°F, enter an
Offset of
– 1.3
to calibrate the sensor to the measured value.
RTD inputs require either sensor calibration or an estimated offset correction for wiring
resistance. Cable length and size affects RTD sensor accuracy. Use the following
information for a 100 ft. (30.48 m) cable as a guideline for entering an offset. For shorter
cable, scale the offset linearly. For example, for a 50 ft. cable, use half the offset shown
below.
RTD sensor Offset for 100 ft. (30.48 m) cable
22 AWG 18 AWG
Platinum 1kOhm at 32°F (0°C) (0.00375
TCR)
-1.5 -0.59
Nickel-iron 1kOhm at 70°F (21°C) -1.1 -0.43
Platinum TS-8000 1kOhm at
32°F (0°C) (0.00385 TCR)
-1.5 -0.59
Balco (nickel-iron) TS8000 1kOhm
at 70°F (21°C)
-1.4 -0.56
Cable resistance for signal and
ground wires (ohms)
3.1 1.24
Analog Output (BAO) You can use the Offset value (positive or negative) to calibrate an output, but you generally
do not need to. If used, the driver adds the offset value to the wire input value before
performing any scaling calculations to determine the TV-MPCXP1628-NR's output.
Binary Input (BBI) Polarity determines the microblock's present value when no signal is received from the
equipment.
When no signal is received from the equipment, if Polarity is set to:
normal — present value is off
reversed — present value is on
Binary Output (BBO) Polarity determines the TV-MPCXP1628-NR's output based on the control program's signal
to the microblock.
When the control program's signal to the microblock is on , if Polarity is set to:
normal — output is on
reversed — output is off
NOTE Regardless of Polarity , the output will be off if the TV-MPCXP1628-NR loses power.