Engineering Documentation

Table Of Contents
Appendix A Discontinued Products
Modular Building Controller/Remote Building Controller (MBC/RBC)
125
-3002
169 | 231
Analog Input Powered Devices
Approved sensors drawing less than 50 mA can be powered by the MBC/RBC analog
input (AI) connections. Sensors requiring more power must be powered by an external
source. The external source can be connected to the same AC line as the MBC/RBC
power supply as long as it is only used to power low voltage devices (less than
30 volts).
Analog Output Powered Devices
No analog output devices can be powered by the MBC/RBC analog outputs.
Class 1/Class 2 Separations
High voltage (and other non-Class 2) Point Termination Modules (PTMs) must be
placed in the upper right module slots of the field panel. All other PTMs must be
placed on either the left rail of the field panel or below the high voltage modules.
Multiple MBCs/RBCs on One Power Source
The following table shows the number of MBC/RBCs allowed on a single three-wire
(ACH, an ACN, and Earth Ground) circuit if local code permits.
Number of MBCs/RBCs Allowed on a Single Three-Wire Circuit.
Circuit Breaker Size
1
Maximum Vales for Concentrated
Loads
Maximum Values for Evenly
Spaced Loads
Length
2
MBC/RBC Length
2
MBC/RBC
15 amp (No.14 AWG THHN) 75 ft
(22.87 m)
7/10 100 ft
(30.48 m)
7/10
20 amp (No.12 AWG THHN) 115 ft
(35.06 m)
7/10 130 ft
(40.63 m)
7/10
1)
Assumes minimum voltage of 102 Vac at circuit breaker and 5 Vac maximum voltage drop (97
Vac at loads). See Class 1 power trunk information in the Wire Specification Tables section of
Chapter 1.
2)
Conduit length from MBC/RBC to MBC/RBC.
Metal Oxide Varistors (MOVs)
Line Voltage Receptacle
V150LA20A MOVs are factory-installed on all MBC/RBC service box receptacles.