Bradford-White Corp BRHHH, BRHHV warranty External Control Connections, Wiring Diagrams

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The second menu “Add” has to do with the N2 address. Pressing enter when “Add” is displayed will display “255”, which stands for 255 unique addresses. The up and down arrows change this value, and enter saves the value if it is changed.

Changing the “Add” value will have no affect on the Brute Magnum, unless a communications card as been built onto the unit. If a Brute Magnum unit has been ordered with an optional communications card, more menus will be active, and the unit will come with separate instructions.

5.7External Control Connections

Brute Magnum units are built with a selector

switch and a terminal strip to allow the Brute Magnum

to receive a 0-10VDC signal from an external controller (such as a building automation system or multiple boiler control).

When the selector switch is in the “Brute Magnum Control” position, the Brute Magnum will be modulated by the unit’s factory-mounted modulating control.

When the switch is in the “External Control” position, the unit look for a 0-10VDC signal from an external (field-supplied) controller.

To interlock the external boiler control with the Brute Magnum, the call for heat signal MUST be connected to the field interlock terminal strip on the Brute Magnum (shown in Figure 29). Be sure to remove the factory-installed jumper between the field interlock terminals. The 0-10VDC modulating signal MUST be connected to external control terminal strip,

located to the right of, and behind the front panel. The terminal strip is labeled “0-10VDC +” and 0-10VDC –” to indicate which terminal received the hot signal

(+)and which terminal receives the common signal (-) from the controller.

The Brute Magnum unit will modulate between 2.23V and 10V (for 25% and 100%, respectively). Anything less than 2.23 volts will result in 25% of full fire.

For the external control to modulate the Brute Magnum, the selector switch on the front panel must be in the “External Control” position.

Important Note: DO NOT MAKE/BREAK Brute Magnum LINE VOLTAGE TO SIGNAL CALL FOR HEAT. A “call for heat / end call for heat” MUST be connected to the field interlock terminals. The Brute Magnum does not recognize 0 volts as a signal to shut off. If the call for heat is not connected between the field interlock terminals, the Brute Magnum will remain in low fire when it sees 0 volts as a modulating signal.

Caution

Brute Magnum supply voltage must not be disengaged, except for service or isolation, or unless otherwise instructed by procedures outlined in this manual. To signal a call for heat, use the 24V field-interlock, as shown in the wiring diagram(s).

Some Brute Magnum components are designed to have constant voltage during normal operation. If Brute Magnum supply voltage is toggled as a call for heat signal, premature failure of these components may result.

5.8 Wiring Diagrams

Caution

Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation. Verify proper operation after servicing.