Benchmark 2500 - 3000 Boilers
CHAPTER 10. BOILER SEQUENCING TECHNOLOGY
OMM-0094_0E
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
Page
127
of
204
GF-137
Ph.: 800-526-0288
03/20/2014
10.3.5 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. See the C-More Controller User
Manual, OMM-0032, GF-112 and ProtoNode User Manual, OMM-0080, GF-129 for more information.
Step 1: Direct Wired Header Sensor Wiring
1. On the MASTER Unit, Connect the Header Temperature Sensor (
AERCO PN 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 downstream of the LAST 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.
Step 3: Configure ALL C-More Units
On ALL Boilers:
1. Go to the
Configuration Menu
and set the
BST Menu
item to
Enabled
.
2. Go to the
BST Menu
and set the
BST Mode
item to
BST Slave
(for now) .
On MASTER only:
3. Go to the
BST Setpoint
item and enter the Failsafe Setpoint.
4. Go to the
BST Setup Menu
item and set to
Enabled
.
5. Go to the
BST Setpoint Mode
item and select
Remote Setpoint
.
6. Go to the
Head Temp Source
item
and select
FFWD Temp
.
7. Go to the
BST Remote Signal
and select either
4-20ma
or
0-20ma
.
When ALL C-More units have been configured
:
8. Go to the
BST Menu
of the desired
Master
unit
and set the
BST Mode
item to
BST MASTER
.
Temp Sensor PN 61040
Header Temp Sensor
I/O Box
I/O Box