......Result of learning ... want
- Fuse - to protect against short circuit, and controller destruction.
- Contactor - to fully isolate batteries (prevent pack destruction if left on accidentally)
- Seat switch - which uses contactor to isolate batteries, if no-one is sitting on the Kart.
- Big Red Kill switch - uses contactor to isolate batteries, in emergency
- Brake microswitch - preventing acceleration while braking.
- A "Contactor" gives perfect mechanical full isolation.
- Kilovac EV200 (US$65) will break over 4000A at 36volts.
- Gigavac GX200 (US$??) will do the same, maybe cheaper.
- Takes up to 12ms to release (so too slow to prevent life-threatening injury).
......Learned about circuit breakers
- Can be used as a "disconnect" switch.
- There are a range of excellent circuit breakers, designed for 12volts, and 24 volts (car applications) ... but these are "thermal" ... and may allow "over current" for some considerable time before they will switch off.
- Really only considered as "slow short-circuit" protection.
- They won't protect batteries.
- Seperate fuse is required.
- Need seperate "Over Current" protection (seperate device).
A battery system of 12 to 48 volts works fine with a circuit breakerrated up to 160 volt d.c. - Search "DC Circuit Breaker" on ebay.com
- Best here = http://www.solarseller.com/dc_circuit_breakers__dc_circuit_breaker_ul_listed_to_125_volts_dc.htm
- Alternative (more expensive) supplier of the Airpax CD-125 type = http://www.cloudelectric.com/product_p/cb-cd125-24.htm
- Poorer example = a 60A breaker http://au.farnell.com/eta/4130-g211-k4m1-70a/circuit-breaker-70a/dp/8567190 takes 1/2 second at 600A to blow !!! $45.70
- Airpax CF-125 breaker (UL listed up to 48 volts, amperage range select 10A through to 110A) ... eg $39 for 60A.
......Fuses
- ANL fuses are OK for low voltage (under 80 volts).
- On www.ebay.com.au - search for "ANL Fuse"
......Learned about Semiconductor switches
- Using Mosfets ... to try and shut down the voltage faster than a physical contactor ...
- .... see UQ design for "Sunshark" ...
- ... but in reality, this is just duplicating the mosfet control in the controller (ie no more reliable than the mosfets in the controller) ...
- ... and doesn't give full electrical isolation.
- Therefore is not useful !
