Critical Environment Technologies LPT-M, Руководство по эксплуатации

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32 © 2020 All rights reserved. Data subject to change without notice.
LPT-M - Operation Manual Rev. B | 2020.11
5.7.3 ESH-A Remote Sensor Wiring Connection
Each ESH-A is given the same serial number as the device it is being connected to. Make sure to
connect the ESH-A to the LPT-M that has the same serial number or the system won’t work.
Four-conductor, 16 AWG stranded shielded cable is required for the remote sensor wiring. This
wiring should be run in a conduit, separate from the signal output, and
should not exceed 61 m
(200 ft). The voltage at the remote sensor (Red V+ to Black GND) should be 24 VDC. If this voltage is
not met after installation, the wrong gauge wire may have been used or the wiring run is too long.
Wiring Example: ESH-A Remote Sensor
The maximum length of wire between the ESH-A Remote Sensor and the transmitter
should not exceed 61 m (200 ft).
5.7.4 Modbus® Wire Gauge vs Run Length
This table shows the maximum cable length between the LPT-M and the BAS / DDC controller for
normal installations.
SUPPLY VOLTAGE
RS-485 BUS
IMPEDENCE
WIRE GAUGE (AWG)
MAXIMUM CABLE
LENGTH
22 VDC minimum
on board termination
resistor available (J5)
low capacitance
shielded wiring,
18 AWG
601 m (2000 ft) at
19,200bps