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Benchmark with Edge [I]: Operation-Maintenance Manual
SECTION 6
– MODES OF OPERATION
OMM-0145_A99
• GF-218 • 9/18/2019 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page
101
of
157
Direct Drive Mode Setup Instructions
4.
If
Network
was selected in the previous step, the
Unit Address
parameter appears. Enter
a valid Comm address in this parameter.
Refer to
Modbus Communication Manual
(OMM-0035, GF-114) for additional information.
6.5 AERCO CONTROL SYSTEM (ACS)
NOTE:
ACS is for installations with between 17 and 32 boilers. It utilizes only RS-485 signaling to the
boiler. For installations with 1 to 16 boilers Boiler Sequencing Technology (BST) is
recommended. See Section 7:
Boiler Sequencing Technology
.
The
ACS
mode of operation is used in conjunction with an AERCO Control System. The
ACS
mode is used when it is desired to operate multiple units in the most efficient manner possible.
For this mode of operation, an ACS Header Sensor must be installed
between 2 and 10 feet
(0.61 and 3m)
downstream of the
last
boiler in the boiler plant's supply water header.
ACS can control up to 32 boilers via Modbus (RS-485) network communication.
For ACS programming, operation, and Header Sensor installation details, see the
ACS
Operations Guide
(OMM-081, GF-131). For operation via an RS-485 Modbus network, refer to
Modbus Communication Manual
(OMM-0035, GF-114).
To enable the
ACS
mode:
ACS Mode Setup Instructions
1. As a prerequisite, verify that the unit is
not
a BST Client or Manager. Go to:
Main Menu
→
Advanced Setup
→
BST Cascade
→
Cascade Configuration,
Unit Mode
=
Off
.
2. On the Controller, go to:
Main Menu
→
Advanced Setup
→
Unit
→
Application
Configuration
.
3. Press
Unit SH Operating Mode
parameter
and choose
Direct Drive
.
4. Press the
Remote Signal
parameter and choose
Network
.
5.
Press the
Baud Rate
parameter and choose
9600
.
NOTE:
See Section 2.11.1 in the
Benchmark 750-6000 with Edge [i]: Install-Startup Manual
(OMM-
0144, GF-217)
for field wiring instructions.
6.6 COMBINATION CONTROL SYSTEM (CCS)
NOTE:
The ACS can be utilized for a Combination Control System.
A Combination Control System (CCS) is one that uses multiple boilers to cover both space-
heating and domestic hot water needs. The theory behind this type of system is that the
maximum space-heating load and the maximum domestic hot water load do not occur
simultaneously. Therefore, boilers used for domestic hot water are capable of switching