'Best' way to run a 24v fridge

[ditchcrawler]

I'm glad someone else said this. It's been stated on here upteen times but still people choose to disbelieve it. Every time I see that "But I turn the fridge off at night" I burst out laughing. I've given up on that one.

 

I am glad this came up, I have a LEC 240 volt fridge and so far I have been unable to find a thermostat. there is a knob with 1-6 on it but I can't find the sensor. I suspect that it may actually be a time space ratio timer. When I started playing, improving insulation, cooling the condenser, I found that the internal temperature dropped and to reduce the power consumption I wound the knob back to end up with the same internal temperature as day one, but with less compressor running time.

What does the panel think ?

[Robin2]

I am glad this came up, I have a LEC 240 volt fridge and so far I have been unable to find a thermostat. there is a knob with 1-6 on it but I can't find the sensor. I suspect that it may actually be a time space ratio timer. When I started playing, improving insulation, cooling the condenser, I found that the internal temperature dropped and to reduce the power consumption I wound the knob back to end up with the same internal temperature as day one, but with less compressor running time.

What does the panel think ?

 

I'd like to improve the insulation on my fridge/freezer but I can't see where the cooling radiator is as all three sides are just flat panels. And it looks like the whole thing was dropped into the steel casing from the top so I can't take the sides etc off.

[Tony Brooks]

You can use your multimeter to optimise the engine rpm for charging. Connect the meter to read volts and start the engine. increase RPM until there is no increase in voltage then reduce RPM to the minimum that maintains this voltage. If you have a tachometer note the reading - this RPM will give the optimium charge rate.

 

There will be avery small increase in fuel consumption but a much larger increase in charging rate. An increase from 12.9V to to 13.3V represents possibly a 40% increase in charge current.

 

My 'modern' engine (tick-over 850rpm, max 3000rpm) charges best at 1500rpm and cruises at 1600rpm; my Gardner 3LW (tickover 380rpm, max 1200rpm) charges best at 500rpm and cruises at 750rpm. I often cruise at the lower, best charging rate speed.

 

You can also use your voltmeter to measure voltage drop across each cable, terminal and relay or diode between the alternator amd the battery post.

 

Alan

 

I am sorry but the first part is juts plain wrong once the system is in acceptance - that is where the volatge regulator is controlling the current. Also during bulk when the alternator's design is limiting the current by depressing the charging volatge the voltage measured will vary throughout that phase of charging, gradually increasing as time goes on.

 

I agree with the sentiment though but the only way to achieve maximum charge throughout charging is to use an ammeter and adjust the engine speed to give maximum amps. The speed will have to be decreased as time goes on otherwise you will be wasting fuel.

 

Going on the voltages quoted I suspect Alan's batteries are very well discharged.