GMX Series


The GMX Series Time Switches are universal, electromechanical time controls. They are a low cost alternative for applications that do not require more than 21 Amp or 2 HP @ 240 VAC. The unit is mounted in a UL Type 1 or UL Type 3R outdoor enclosure. The GMX is a light-duty commercial time switch ideal for 24 or 120 VAC single phase applications, such as lighting control, heating, air-conditioning, pumps, motors, fans, agricultural facilities and general electrical circuits.

  • Series Overview
  • Model Lineup
  • Specifications
  • Resources

• 21 Amp SPDT Switch

• Type 1 indoor or Type 3R outdoor enclosure

• Manual 3-way override

• Captive trippers with 15-minutes intervals on 24-Hour models and 2-hour intervals on 7-Day models

• True clock face, easy to set

• Finger-safe terminals

• Enclosure provides space for field added contact or other accessories

• Synchronous drive or quartz drive with battery backup

Product Ratings
Model24-Hour or 7-DayEnclosureVolts ACBattery BackupSwitch RatingMinimum On-Off Time
GMXQT-I-12024-hourType 1 Indoor 120 VAC, 50/60 HzYesSPDT15 minute
GMXQT-O-12024-HourType 3R Outdoor120 VACYesSPDT15 minute
GMXST-I-12024-HourType 1 Indoor120 VACNoSPDT, 21 Amp15 minutes
GMXST-I-24024-HourType 1 Indoor240 VACNoSPDT, 21 Amp15 minute
GMXST-O-12024-HourType 3R Outdoor120 VACNoSPDT, 21 Amp15 minutes
GMXST-O-2424-HourType 3R Outdoor 24 VACNoSPDT, 21 Amp15 minutes
GMXST-O-24024-HourType 3R Outdoor240NoSPDT 21 Amp15 minutes
GMXQW-I-247-DayType 1 Indoor 24YesSPDT, 21 Amp2 hours
GMXQW-I-2407-DayType 1 Indoor240YesSPDT, 21 Amp2 hours
GMXSW-I-1207-DayType 1 Indoor120NoSPDT, 21 Amp2 hours
GMXS-O-247-DayType 3R Outdoor24 VACNoSPDT, 21 Amp2 hours
GMXSW-O-1207-DayType 3R Outdoor120 VACNoSPDT, 21 Amp2 hours
GMXSW-O-2407-DayType 3R Outdoor240 VACNoSPDT, 21 Amp2 hours

Switch Rating: 21A Resistive @ 120-250 VAC

1HP @120 VAC

2HP @ 240 VAC

1,350W Tungsten @ 240 VAC

Wiring Connections: Screw terminal accepts up to #12AWG


Operating Temperature: -40˚F to 185˚F (-40˚C to 85˚C)

-4˚F to 131˚F (-20˚C to 55˚C) with battery


Operating Humidity: 0 to 95% non-condensing

Enclosure Dimensions: 10"H x 6.50" W x 3.75" D

Battery Backup Option: 7 Days

Supply Voltage: 24, 120, 240 VAC, 60 Hz models

Quartz: 120, 240 VAC 50/60 Hz

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