Option 8 Remote Setpoint: Modbus Header Temp Sensor & Modbus Setpoint Drive Via Protonode - Watts Aerco Benchmark BMK750 Operation And Service Manual

Benchmark with Edge [I]: Operation-Maintenance Manual
SECTION 7 – BOILER SEQUENCING TECHNOLOGY
Option 8 Remote Setpoint: Modbus Header Temp Sensor & MODBUS
7.3.8
Setpoint Drive via ProtoNode
OPTION 8 Instructions: Remote Setpoint, Modbus Header Temp Sensor & Modbus Setpoint
Drive
OPTION 8 Step 1:
MODBUS
1. Connect the Modbus Transmitter terminal Pin B to the RS485+ terminal, and Pin A to the
RS485- terminal on the I/O Board of any Boiler unit, using shielded pair 18 - 22 AWG cable.
2. Connect the shield to any SHLD terminal on the I/O Board.
3. Connect the Header Temp Sensor to pins 2 and 3 of the Modbus Transmitter using
shielded pair 18 - 22 AWG cable.
4. Install a jumper wire between pins 1 and 2 of the Modbus Transmitter.
NOTES:
•
Polarity must be observed for the RS485 connections.
•
Connect the shield to any SHLD terminal on the I/O Board.
•
The Header Temp Sensor must be installed between 2 and 10 feet (0.61 and 3.1m)
downstream of the last boiler in the plant's supply water header.
•
There is no polarity to be observed. The ground for the shield is at the power supply
ground. The sensor end of the shield must be left free and ungrounded.
HEADER TEMP SENSOR
OPTION 8 Step 2: CONFIGURE AND CONNECT SSD DEVICE (PROTONODE)
1. Connect the ProtoNode per the instructions in one of the ProtoNode FPC N34, FPC-N35
Manuals:
•
For FPC-N34 (P/N 64129) or FPC-N35 (P/N 64130), see OMM-0107 (GF-150).
•
For FPC-N34 (P/N 64168) or FPC-N35 (P/N 64169), see OMM-0150 (GF-150_B).
OPTION 8 Step 3: CONNECT BOILERS IN DAISY CHAIN
1. Connect the boilers in a daisy chain, as shown below.
OMM-0145_D • GF-218 •
11/2/2020
HEADER TEMP SENSOR WIRING – ANY BOILER
MODBUS TRANSMITTER
Continued on next page
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I/O BOARD
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