FRA Rules

**leorcc** · 12th November 2003, 17:41

While on the subject on maximum voltage, I for one think 60V is approuching the very dangerous voltages for people that are not well versed in electronics.

I think 36V to 48V should be more than adequate for fighting robots, what do you think?

Bye,
Leo

12th November 2003, 22:47

If the receiver is switched off the robot must failsafe

This makes the built-in failsafes of PCM-receivers useless. You will have to add external failsfes nevertheless.

**big_nipper** · 13th November 2003, 07:20

Holger, I dont agree. 4QDs that we uses will stop if the rx power is lost as the speed input is then zero. What can happen first is a sudden direction change when the direction power is lost before the decel ramps return the speed to zero. In anycase we have failsafes after the rx just in case. What is worrying is that if the failsafes in the PCM are not active (as has happened to ours on more than one occation under the tech check) then it will stay at the last set speed.

13th November 2003, 11:09

In your case, the 4QD interface will provide the external failsafe function. Not too much of a problem for the drive system, as many speed controllers do. It is more a problem with the weapon system. where the controllers normally arent that intelligent.

You are right, if the PCM failsafes get stuck, an external solution wont help you. Id say: Buy a good radio system

. We luckily never had that problem with our JR X-388s.

**john_frizell** · 13th November 2003, 14:34

Leo,

I agree with you - an upper limit of 48 volts should be plenty. The RW limit of 60 can probably be interpreted as 48 in practice since they specify that the 60 volt limit applies to a freshly charged battery pack which means that a series string of 5 12 volt batteries would go well over it. Im not aware of anyone using voltages higher than 48. In fact, I dont think Ive yet seen a 48 volt robot.

John
Terror Turtle/Steel Sandwich

**wenman** · 26th December 2003, 11:28

I have a question on fail the safe lighting.
4.3 in addition to the main power light showing the main power is activated. It should also indicate if the robot is in failsafe, off or zero position.
What should the light do?
Should it flash on and off?
Change colour?
Or would a second light next to it be acceptable? (This would be a lot easier than the other two options and just as clear).