Pumps, water heaters, parking lot lights and ventilation fans often need a heavy-duty mechanical time clock that survives outdoors and doesn't care what voltage is on site. The Intermatic GM40AV-W is a 7-day electromechanical time control rated 40 A that detects any supply from 120 to 277 VAC on its own, in a NEMA 3R outdoor plastic enclosure.
Why electricians pick it
- Auto-voltage: detects 120 to 277 VAC with no DIP switch or selector pins to set.
- 40 A contacts in a DPDT configuration for high-amperage loads, including 240 V loads that need both legs switched.
- 7-day dial for different schedules on weekdays and weekends.
- NEMA 3R plastic enclosure for outdoor or damp mechanical rooms, rated -40°F to 131°F.
- LED indicators show power and status at a glance.
Specifications
| Spec |
Detail |
| Brand |
Intermatic (Grasslin GM40 series) |
| Model / SKU |
GM40AV-W |
| Type |
Electromechanical time control, 7-day |
| Voltage |
120-277 VAC auto-detecting, 60 Hz |
| Rating |
40 A |
| Switching |
DPDT (SPDT/DPDT per listing) |
| Time setting |
2 hours to 7 days |
| Enclosure |
NEMA 3R outdoor, plastic |
| Operating temperature |
-40°F to 131°F |
| Indicators |
LED power / status lights |
Pro tip from the counter
On a 7-day dial the shortest ON or OFF period is about 2 hours, per Intermatic's listing. For short daily cycles, like a 30-minute circulation pump run or a 15-minute fan purge, use the 24-hour GM40AV instead; the 7-day version can't set them accurately.
Best for: pool and well pumps, water heaters, parking and sign lighting, ventilation and exhaust fans, agricultural and commercial loads on 120 V to 277 V
Ships across Canada from Vaughan, ON. Contractors can get trade pricing through a quote or by calling (905) 553-7171.