Benchmark Series Boilers Pre-Installation Electrical Power Guide
TAG-0048_Q
• 5/16/2023 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page
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4. BOILER WIRING
A dedicated protected circuit,
sized for the amperage values below
, should be provided to the boiler.
No other electrical devices should be permanently wired on the same circuit.
An emergency switch (electrical shutoff) must be wired in series with power to the unit. Connecting an
emergency shutoff switch (E-stop) to the main power terminals of the boiler is the safest way to
disable and un-power the unit. Use of the remote interlock, located on the I/O board, is not
recommended since it does
not
cutoff power within the unit, it only disables it. Under no circumstance
should the remote interlock of the BST Manager unit be used as an emergency switch for the plant.
Multiple Unit Wiring:
When multiple units are installed within the same mechanical spaces, electrical
code requirements call for a single electrical shutoff for emergency use. It is the responsibility of the
electrical designer to comply with local codes and regulations affecting an individual installation.
The following table lists the input power requirements for all Benchmark boilers, including the diagram
number of each model’s corresponding schematic diagram:
DOMESTIC UNITS
INTERNATIONAL UNITS
BMK Model Diag. Voltage/Phase/Frequency Amps Wires Diag. Voltage/Phase/Frequency Amps Wires
750
– 1000
1a
120V / 1
/ 60 Hz@
15 A
3
1b
220V / 1
/ 50- 60 Hz
20 A
3
1500
– 2000
20 A
2500/3000
2
208V / 3
/ 60 Hz
20 A
5
3a
480V / 3
/ 60 Hz
15 A
4
3b
380-415V / 3
/ 50- 60 Hz
15 A
4
4000/5000N
7
208 V / 3
/ 60 Hz
40 A
4
6a
480V / 3
/ 60 Hz
20 A
4
6b
380-415V / 3
/ 50- 60 Hz
20 A
4
5000/6000
4
208V / 3
/ 60 Hz
30 A
4
5a
480V or 575V / 3
/ 60 Hz
20 A
4
5b
380-415V / 3
/ 50-60 Hz
20 A
4
For applicable wiring connections, refer to the schematic diagrams below.
Diagram 1a - BMK750
– 2000: 120 V / 1
/ 60 Hz Wiring Schematic
– 3 Wire – DOMESTIC
120 V / 1
/ 60 Hz
DISCONNECT SWITCH
1 POLE 20 AMP
1 POLE 20 AMP
CIRCUIT BREAKER
