Murphy Generator Panel MGC921 Series Specifications

FRANK W.

Generator Panel

Description
The MGC921 provides economical engine and
generator control for applications not requiring
NFPA-99 or NFPA-110 approval. Models are
available for Manual or Automatic start designed
for 3-phase, 4-wire or 1-phase, 3-wire genera-
tors. Models MGC921 feature mechanical
SWICHGAGE ® s for engine oil and coolant tem-
perature. Models MGC921E feature EGS elec-
tric SWICHGAGE ® s. The panels are housed in a
13 x 10 x 11 in. (330 x 254 x 279 mm) shock
mounted NEMA 1 drip-proof enclosure. Current
transformers (CT's) are not included.
Features
Auto-Start Panel includes the following features.
• ASM150, auto-start controller with:
– Optically-isolated noise resistant inputs.
– Outputs for fault annunciator.
– Crank/rest cycle timer, 4 to 25 sec. adjustable.
– Shutdown time delay, 1 to 25 seconds
(adjustable), locks out low oil pressure
and high temperature on start-up.
– Crank disconnect and overspeed
sensing operates from a magnetic pickup
signal (requires 2 Vrms minimum).
• Auxiliary starter relay. Contact rating: 12 volt,
40 amp/24 volt 16 amp.
• Oil pressure SWICHGAGE ® , 2-1/16 in. (52
mm) dial, 0-100 psi (0-689 kPa) [6.89 bar].
• Temperature SWICHGAGE ® , 2-1/16 in (52
mm) dial, 130-250°F (54-121°C), 12 ft.
(3.7 m) capillary.
• TEST-OFF-AUTO selector switch.
• Two 2-1/16 in. (52 mm) dia. holes, plugged.
®
MFR.
Manual Start Panel includes the
following features.
• Power OFF-ON toggle switch and start
push button.
• 518APH TATTLETALE
• Auxiliary starter relay. Contact rating: 12 volt,
40 amp/24 volt 16 amp.
• Oil Pressure SWICHGAGE
dial, 0-100 psi (0-689 kPa) [6.89 bar].
• Temperature SWICHGAGE
dial, 130-250°F (54-121°C), 12 ft. (3.7 m)
capillary.
• Two (2) 2-1/16 in. (52 mm) diameter holes,
plugged.
AC meters
• AC voltmeter, 3-1/2 in. (89 mm) dial, ±2%
full scale (specify range: 300 V or 600 V).
• AC ammeter, 3-1/2 in. (89 mm) dial, ±2%
full scale (specify range: 50 to 4000 A).
• AC frequency meter, 120 V, 3-1/2 in. (89
mm) dial, ±0.6% Hz, 45–65 Hz.
• Frequency meter rheostat.
Options
AC ammeter-voltmeter phase selector switch* .
Requires 2 additional CTs.
Hourmeter, 2 in. (51 mm) dial, 5-digit.
Battery voltmeter, 2 in (51 mm) dial (range
determined by battery voltage).
Battery ammeter, 2 in (51 mm), 60-0-60.
*Standard (included) with 3-phase models.
MGC921 Series
Available in Manual or Auto Start
– 12 or 24 VDC Battery Voltage
– Single Phase or 3-Phase
Compact
Full Featured

Specifications

Auto-Start Panel
• Power Requirements:
– 12 VDC battery for 12 V models.
annunciator. – 24 VDC battery for 24 V models.
®
• Inputs: Ground or positive inputs for high
temperature or low pressure sensors.
® , 2 in (51 mm) • Outputs:
– Auxiliary starter relay. Contact rating:
12 volt, 40 amp/24 volt 16 amp.
® , 2 in (51 mm)
– 300 mA transistors for fault annunciation
• Operating Temperature: -4 to 140°F (-20 to
60°C).
• Cycle Crank Timer: Up to 8 attempts.
Recrank on false starts (fixed 30 seconds).
• Crank/Rest Cycle Timing: 4 to 25 seconds
(adjustable).
• Shutdown Time Delay: 1 to 25 seconds
(adjustable). Locks out low oil pressure and
high temperature on start up.
• Crank Disconnect Speed Setting:
From 30 to 8500 Hz.
• Overspeed Trip Point Setting:
From 30 to 8500 Hz.
• Magnetic Pickup Input:
Requires 2 Vrms minimum.
Manual Start Panel
• Power Requirements:
– 12 VDC battery for 12 V models.
– 24 VDC battery for 24 V models.
• Operating Temperature: -4 to 140°F
(-20 to 60°C).
MGC-95093B
Revised 03-00
Catalog Section 75
(00-02-0134)