What battery cable size should I use?
When connecting a DC hydraulic power pack to the battery it is important to get the cable sizing correct. The battery cable will carry high currents and they must be sized to minimise voltage drops. When a DC powerpack is running at full load currents up to 300 amps can be required.
Maximum current draw of your DC powerpack can be estimated as follows, but for exact current figures the dc motor performance curves must be referred to.
500 Watt | 800 Watt | 2kW | 3kW | |
12VDC | 100A | 130A | 250A | |
24VDC | 55A | 70A | 150A | 275A |
On many vehicles and trailers the battery can be mounted some distance from the power pack the length of the battery cables must be considered. This is because the voltage drop calculation is proportional to the resistance of the battery cables and therefore the amount of copper used.
These figures are based on the use of a Tri-rated cable (BS6231) as this a flexible and high temperature multi-stranded high current cable. Battery cable must be terminated with crimped ring ends, ensuring these are securely tightened onto battery and dc hydraulic power pack terminals.
Failure to adhere to these guidelines can cause excessive voltage drop in the cables at full load current. This can cause damage to the power pack and also result in dangerous overheating of the cables and connected equipment. The use of a suitably sized fuse is recommended.