Something for clarification, no doubt.
From other forms of racing, the master switch is to remove the battery(isolate) from the rest of the system AND kill the motor. magneto guys love this.
However, I have in the past done almost exactly what JHN wants to do by either supplying a small battery for the data recorder seperate or using a small .3 amp fused circuit to the DR. If a small fuse is used and placed as close to the master switch or on it the argument could be made that it poses no threat.
I am not in agreement with the rules about having the switch mounted at the extreme end of the vehicle, if the battery is in the center then the length of wire is vulnerable to the switch. Should this wire become damaged in the incident, you have no way of isolating the battery from the damage. This is a very real concern because the wire is probably of enough size to carry a decent amp load to the starter and potentionally cause enough heat to cause burning or start something else burning.
The DR situation is easy, if need be add additional battery, NiCad from RC car works very well and doesn't need charging but once a weekend. As for the coolant pumps, my opinion is mechanical drive from motor, motor stops so does the water, except for leaks.
John
