Benchmark 750 – 1000 Boiler User Manual - INTERNATIONAL
CHAPTER 9. BOILER SEQUENCING TECHNOLOGY
Page
122
of
170
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
OMM-0119_0A
11/03/2016
Ph.: 800-526-0288
GF-130-I
9.3.5 Option 5 - Remote Setpoint with DIRECT WIRED Header Sensor AND 4-
20ma Setpoint Drive
NOTE:
Both Header Sensor AND 4-20ma Direct Drive must be wired.
Step 1: Direct Wired Header Sensor Wiring
1. On the MASTER Unit, Connect the Header Temperature Sensor (P/N
61040
) to the Feed Forward
(FFWD) terminals on the P-1 Harness Via the terminal block labeled
Header Temp sensor
in the I/O
Box.
NOTES:
•
The header sensor must be installed between 2 and 10 feet (0.61 and 3.1m) downstream of the
LAST Heating Boiler in the plant’s supply water header.
•
Shielded pair 18 - 22 AWG cable is recommended for header sensor wiring.
•
There is no polarity to be observed.
•
The ground for the shield is at the “SHLD” terminal in the I/O the Box.
•
The sensor end of the shield must be left free and ungrounded.
Step 2: Direct Wired 0-20ma or 4-20ma Wiring
1. Connect the 4-20ma or 0-20ma terminals from the Direct Drive source to the Ain+ and Ain- terminals
on the Master Unit’s I/O Box.
NOTE:
•
Shielded pair 18 - 22 AWG cable is recommended for this connection. Polarity must be observed.
•
The ground for the shield is at the driver signal source.
Temp Sensor P/N 61040
Header Temp Sensor
I/O Box
I/O Box
