I had a mishap a few days ago with a fuse. There is a little fuse inside of the Panel that is connect to the Bilge Pump switch. Anyone happen to what AMP it is.
One other thing. Anyone happen to have a list of the fuses used on the Catalina 310. There seems to be a number of them.
Cheers
2 Old Pirates.
If that is the only fuse in the bilge pump circuit then it needs to be sized to the bilge pump manufacturers recommended fuse size. Installing too large a fuse in a bilge pump can lead to a fire in a stalled rotor situation, this is why the bilge pump maker will list the fuse size.
If it is the primary fuse in the circuit, not the secondary fuse, a primary fuse is usually located closer to the battery, it can be sized based on wire gauge ampacity but there must also be a second fuse sized for the pump.
I have posted this before but here is some in-shop testing I did on fuse sizing and bilge pumps..
Guys,
I had a Rule 500 kicking around my shop so I attached it to a battery... Rule recommended a 2.5A (AGC Type) fuse for this pump. If you use an ATC fuse, much more reliable in the marine environment,
with the proper fuse holder, then you'd need to bump to a 3A fuse. The pump is rated at 12V for a 1.9A draw when pumping water and a 2.5A draw at 13.6V when pumping water.
This test was done at battery resting voltage, at charging voltages currents would obviously be slightly higher:
Battery = Group 31 AGM Resting Voltage 12.77V
Test Meter = Fluke 376 Clamp w/Inrush & min/max & Fluke 289
Pyrometer = Fluke Infrared
Test:
12.75V Ran pump dry for 10 minutes and saw 1F rise in case temp (Fluke infrared thermometer)
12.72V - No Load (spinning in air) = 0.7A (inrush/starting current 2.7A)
12.72V - Locked Rotor with 3A Fuse = Blew Instantly
12.71V - Locked Rotor with 5A Fuse = Blew nearly instantly (about 6 seconds)
12.71V - Locked Rotor with a 15A Fuse = No blow 10.9A continuous, pump getting rather warm to the touch after 90 seconds of stall. Discontinued at 2 minutes and 10.7A (heat build up likely caused current to drop a bit)
12.70V - Locked rotor measuring inrush with 5A ATC fuse - Inrush = 10.9A - Fuse blew (separated/burned) but failed unsafely leaving a bit of metal across tabs. This is my first live example of where the AIC (
Amperage Interrupt Current) matters when directly connected to a battery. Scary stuff! I ran the load for approx four additional minutes and the "
failed unsafely" fuse still failed to blow even at 10.7-10.8A pump was very warm when I discontinued. The pumps exterior was approaching 200F at the measurement location and it was starting to give off a burned electrical smell..
Bottom Line: This is why you want a fuse that
will blow with your pump in locked rotor mode otherwise it can continue to heat and then melt and then potentially start a fire.
One of the biggest blunders I see on boats are pumps with grossly oversized fuses for bilge pumps. It is not uncommon for me to see 500GPH pumps with 15A fuses that will never trip even with a stalled rotor.... Not good.. D'oh....