Qmark MUH Series Installation & Maintenance Instructions Manual

Also see for MUH Series: Installation, operation & maintenance instructions Installation, operation & maintenance instructions

Contents

Qmark MUH Series Installation & Maintenance Instructions Manual Manual pdf 4 page image

7. Each heater has a wiring diagram affixed to the inside ofthe access door. Consult this diagram before makingany field connections.8. Single or three-phase power connections may beused with heater models MUH0521, MUH0581,MUH072, MUH078, MUH102, MUH108, and MUH158.These units are factory wired for single-phase operation. Ifthese heaters are for use with three-phased power,reconnect the wires as indicated in the wiring diagramattached to the heater. Additional information can befound by looking at the wiring illustrations in Figures 3a and3b and following the directions shown below.On models MUH0521,MUH0581, MUH072, MUH078, MUH102,and MUH108 (Figure 3a), move only the two wires marked “A1”and marked “B1”; do not move or change any other wiring. Theelement lead wire marked “B1” which is factory connected to thepower terminal block (terminal located closest to the elements)must be moved to terminal “B” on the three-phase terminalblock.The relay (contactor) lead wire “A1” must be moved fromthe end terminal of the power terminal block (terminal clos-est to the contactor or control terminal board) to the “A” termi-nal of the lower terminal block (center terminal).Model MUH158 (Figure 3b) has two three-phase terminalblocks located adjacent to the relays (contactors). Move onlythe two wires marked “C1” and “D1” on each of these two three-phase terminal blocks to terminal “B”. Do not move or changeany other wires.9. Electrical Accessories, either kits or factory-installedoptions, are shown connected by a dash line on theheater wiring diagram.10. 208/240 VOLT HEATER. Interchange transformer redand black primary leads (see wiring diagram) when theheater is to be connected to 208 volts supply.ABLEAD WIRE"B1"ELEMENTSCONTACTOR(OR P2) POWER TERMINAL BLOCKHEATER FRONT LEAD WIRE"A1" 3 PHASE BLOCKTO ELEMENTSABLEAD WIRE"B1"ELEMENTSCONTACTOR(OR P2) POWER TERMINAL BLOCKHEATER FRONT LEAD WIRE"A1"3 PHASE BLOCKTO ELEMENTSFACTORY-WIRED FOR SINGLE-PHASE POWER FIELD-WIRED FOR THREE-PHASE POWERFigure 3a. Wiring Connections for Single-Phase and Three -Phase Power(MUH0521, MUH0581, MUH072, MUH078, MUH102 and MUH108)4