Benchmark 750-3000 Installation & Startup Manual
SECTION 6
– BOILER SEQUENCING TECHNOLOGY
OMM-115_D
•
GF-200
•
5/9/2019
Technical Support
•
(800) 526-0288
•
Mon-Fri, 8 am - 5 pm EST Page 113 of
126
6.3.8 Option 8 - Remote Setpoint with MODBUS Header Sensor AND
MODBUS Setpoint Drive
OPTION 8 - Remote Setpoint With Modbus Header Sensor And
Modbus Setpoint Drive Instructions
NOTE:
Both Header Sensor AND ProtoNode SSD Device must be wired. See the
C-More
Controller User Manual
, OMM-0032 (GF-112) and
ProtoNode User Manual
, OMM-0080
(GF-129) for more information.
Step 1: MODbus Header Sensor
1. Using Shielded pair 18 - 22 AWG cable, Connect the Temperature Transmitter (P/N
65169
)
terminal Pin B to the RS485+ terminal on the I/O Box of any of the Boiler units, and Pin A of
the Temperature Transmitter to the RS485- terminal on the I/O Box of any of the Boiler
units.
2. Using Shielded pair 18 - 22 AWG cable, connect the Modbus Header Temperature Sensor
(P/N 24410) to pins 2 and 3 of the Temperature Transmitter.
3. Install a jumper wire between pins 1 and 2 of the Temperature Transmitter.
NOTE:
•
Polarity must be observed for the RS485 connections. The ground for the shield is at
the “SHLD” terminal in the I/O the Box.
•
The header 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.
Step 2: Remote Setpoint with Network
1. Configure and Connect the SSD Device (ProtoNode) per the
ProtoNode User Manual
,
OMM-0080 (GF-129).
(Continued)
TEMP SENSOR P/N
24410
MODBUS TRANSMITTER I/O BOX
