Solving static electricity problems by grounding the frame

[RyanCahoon]

Originally Posted by ErichKeane

The battery short issue is easily solved by using fuses and circuit breakers. For a competition like this, I've been very surprised that there isn't a rule requiring inline fuses on the positive source lines of all the batteries. Otherwise, the fuses will prevent a short from causing any issue.

There is, that's what the breakers in the power distribution block are for, as well as the 120A main breaker. There'll always be some wire that has to connect directly to the battery, which gives you a risk of an unprotected short.

Originally Posted by ErichKeane

By disallowing the grounding of the frame, FIRST is causing an even more dangerous problem, the situation where a single positive wire contact would could give the entire frame a POSTIVE charge, which, through a human resistor, could cause extreme physical damage.

While I don't think there's any debate that a shorted chassis is bad, as you have pointed out yourself, in order for current to flow through a person and cause damage, they would have to be holding on to a negative connection while they were touching the chassis.

Conversely, with a grounded chassis, if a positive lead touches the frame, you've created a short to negative, meaning a massive current flow, causing the battery to heat due to internal resistance. Hot material expands, and the last thing first needs is a leaking lead-acid battery, much less the fire hazard.

Originally Posted by ErichKeane

There is a very good reason all cars have their bodies/frames grounded, it is for the obvious safety benefits.

Not really, it's more a convenience incentive, that way only one power wire (positive) has to be run to devices, leading to less cable runs.

--Ryan