AERCO Modulex E8 Controls Guide - Manual (Page 65)

PR1: 11/30/12 Page 65 of 112
GF-115-C Modulex E8 Controller and BCM
Operations and Maintenance Manual
OMM-0084_0D
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 • Ph: 800-526- 0288
Y2 Y3 Y4
Y1
SW1 A1
I
0
7 6 5 4 3 2 1
Y2
SEE CHART RESISTOR SETPOINT
160°F
120°F
100°F
140°F
100K OHMS
47K OHMS
22K OHMS
10K OHMS
180°F OPEN
SHORT 80°F
Figure 7-5: Installing Resistor to Change Default Setpoint
7.4 BCM Configured as Primary Controller Utilizing Modbus
NOTE: When the BCM is configured as the primary controller, the E8 will display the
fault code “E200”.
The BCM can be configured as the Primary Controller, instead of the E8, when it is connected
to a Modbus Network. However, the E8 must be disconnected from the e-Bus connection on
the BCM Board (see Paragraph 7.4.3). All Modbus Networks are implemented utilizing a
“Master – Slave” scenario where only one device, the “Master”, can initiate a communication
sequence. However, BCMs can only function as “Slave” devices on a Modbus Network.
Therefore, the BCM must be interfaced to an external controlling “Master”. The “Master” can be
AERCO’s Boiler Management System II (BMS II), AERCO Control System (ACS), or an Energy
Management System (EMS)/Building Automation System (BAS) developed by other
manufacturers.
The following subordinate paragraphs provide descriptions of Modbus Network operation and
required wiring connections between the BCM “Slaves and the controlling “Master” (EMS, BAS).
Detailed information on the Modbus Function Codes, Input/Holding Register Assignments and
other Modbus requirements supported by the BCM are provided in Section 9 of this document.
7.4.1 Operating Scenario
Each Modulex Boiler must be equipped with its own BCM to allow Modbus Network monitoring
and control. An EMS or BAS Master can control the Networked Modulex Boilers utilizing
Remote Setpoint. An AERCO BMS II Master can control the networked Modulex boilers utilizing
a Modbus signal.