Master Bms Ii/Acs Or Ems/Bas Terminating Resistor And Bias; Bcm Controller Terminating Resistor - Watts AERCO EXT Installation, Operation & Maintenance Manual

Ufly Controller and BCM for Modulex EXT
CHAPTER 6: BOILER COMMUNICATIONS MODULE (BCM)

6.6.1 Master BMS II/ACS or EMS/BAS Terminating Resistor and Bias

All AERCO ACS units are equipped with a built-in terminating resistor. Therefore, when the ACS
is the controlling Master, no terminating resistor needs to be added. In addition, ACS contains
two Bias DIP switches which must be activated when the ACS is the controlling Master. See ACS
Manual GF-131, Section 2.6 for additional information on these switches.
When a third-party EMS or BAS is used as the controlling Master, consult the manufacturer's
Technical Manual for termination resistor recommendations.

6.6.2 BCM Controller Terminating Resistor

BCMs can function only as Slave devices on a Modbus Network. Since the Slaves are
connected in a "Daisy-Chain" configuration, the terminating resistor must be enabled only in the
last BCM Controller in the chain. Enabling the terminating resistor is accomplished by
positioning jumper JP2 as shown in Figure 6-13 only on the BCM Board contained in the last
BCM Controller.
Figure 6-13: BCM Loop Termination and Bias
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