Rule RuleMate III 500 GPH Automatic Bilge Pump, 12V DC
- Brand:
- Rule
- Part no:
- RM500B
Image: Fisheries Supply
Where to buy
Specifications
- Rated flow
- 500 gal/h
- Voltage
- 12V
- Current draw
- 1.8 A
The Rule RM500B is a RuleMate III automatic bilge pump rated at 500 gph on 12V DC. Solid-state sensors switch it on when water reaches 2-1/2 inches and off at 5/8 inch, and a check valve cuts the water left behind. It has a built-in thermal cut-off. If debris fouls the sensor, a back-up mode keeps it from running continuously. It draws power only when it is pumping, and it is designed to reach its flow at 12 volts.
Our take
The RuleMate III turns on at 2-1/2 inches of water and shuts off at 5/8 inch, with a check valve to cut what drains back, so it keeps the bilge down to about 5/8 inch. The sensors read water only, so pure oil will not start it.
From our buying guide
Rule and Johnson both say their bilge pumps are not intended for damage control. Flow falls as the discharge head rises, and the length of the hose, its bends and any check valve reduce it further.
Check before you buy:
- The maker's own table shows the flow at head, since how much a pump loses depends on the model.
- An automatic pump also has a manual switch, which ABYC's voluntary 2005 standard calls for.
- You'll fuse it to the maker's figure.