Rule Rule-Mate 1100 RM1100B 12V connections

RM1100B is the 12 V Rule-Mate 1100 with an integrated water sensor. The 1100 GPH name describes open discharge: the manual shows 806 GPH at 1 m head and 554 GPH at 2 m. Hose height and resistance therefore matter before choosing it for a particular bilge. This is a bilge-water pump, not a fuel-transfer pump.

Brown is the automatic positive supply, brown/white is the manual override positive, and black is negative. Connect the control arrangement using the manual's three-position panel or separate automatic/manual diagram. Automatic protection should remain available when the ordinary cabin circuits are switched off. If manual override is not fitted, insulate its unused lead individually; do not leave exposed copper in the bilge.

Use the specified 7.5 A fuse. Rule explicitly discourages circuit breakers for these pumps. The catalog's 4.8 A is the published running draw at 13.6 V; the same table gives 3.8 A at 12 V. Neither number is an inrush measurement. The three canvas terminals preserve the distinct leads, but the planner cannot simulate the internal water sensor or switch logic. A connected automatic lead does not mean the motor runs all day.

Secure the strainer base where water collects, with access to release and clean it. Check material thickness before drilling. Use smooth flexible hose and avoid kinks, unnecessary height and low pockets; rigid pipe can stress the pump outlet. Arrange the outlet and any vented loop for the vessel's heeled waterline. A check valve does not provide anti-siphon protection.

The supplied leads are 16 AWG tinned wire. Size extensions for the complete positive-and-negative circuit and protect sealed joints above bilge water. The manual's distance-conversion column has inconsistencies; establish the real route length instead of trusting a converted column blindly. Terminal limits in the catalog are protection-based planning bounds, not independently published connector ratings.

Introduce clean water into the bilge and confirm automatic start near 63.5 mm depth, discharge outside the boat, and stopping near 16 mm. Test manual override separately, then restore automatic mode. Check voltage at the running pump: Rule specifies at least 10.5 V there. A motor that turns with little discharge calls for inspection of the strainer, hose and discharge head, not a larger fuse. Debris can also trigger the sensor's fallback cycling; clean and retest before accepting that behavior as normal.

Rule-Mate 500–1100 manual: PDF pp. 3–7 cover the exact RM1100B ratings, sensing behavior, three-wire circuits and installation. The downloaded PDF and its SHA-256 are recorded in the marine research ledger.