How many Victors may we have per PDU circuit (assuming, say, each Victor is controlling a BaneBot motor, not a CIM motor?
It is always one motor controller per breaker on the PDB. In some circumstances, you can control multiple motors off of one controller, but you should consult the rules to make sure the motor/controller pair is legal.
Thanks. And, I assume, one PDB per bot?
The one ROBOT battery, Anderson Power Products (or APP) Connectors (p/n SB50), the one main 120-amp (120A) circuit breaker (Cooper Bussman P/N: CB185-120), and the **one Power Distribution (PD) Board **shall be connected as shown in Figure 4-11.
Also, would we be allowed to run a Victor (or any other motor controller) to a 30 amp (or 20 amp) breaker on the power distribution slot?
R46 says that each branch circuit must be "protected by one and only one circuit breaker on the PD Board per Table 4-2. " This table states that a branch circuit with a motor controller must be protected with a circuit breaker value of “up to 40 amps” - would running with a breaker of 30 amps thereby be legal?
Would it work? We would likely run our smaller motors (Banebots) off these. We are aware that we may run two Banebot motors to one Victor (per R51).
We are running seven Victors and a compressor off the Power Distribution Board right now, and are wondering whether there is any way to add on more motors besides this that remains within the rules- are there any other suggestions? We’ve discussed as a team the possibility of replacing some of the motors we have in use with pistons as an alternative if necessary, but like the finer adjustments the motors are able to give us.
Thanks for the help!
30 amps on a victor is entirely legal. That should free up the ‘small’ spots on the PD board.
Also, your compressor can be on a 20 amp breaker. If that was in a 40 amp ‘large’ slot, that’ll free another one up.
Thanks! Really appreciate the help. We were indeed running the compressor off the 40 amp slot (as well as the other seven victors mentioned). Based on the suggestions, we’ll try some different configurations.
Compressor needs to be run from a 20 amp breaker only. You may run any motor from a 20 amp breaker but why would you if you need the max current for your drive. If you are running out of PD, you are likely draining your battery and will brownout critical power supplies like the cRio, Radio and DSC. Remember that the DSC stops making PWM and other digital interface signals below 5.5 volts in and the PD supplies for cRio, camera and radio stop at 4.5 volts input.
Al’s point about total power consumption on the robot isn’t a hypothetical situation.
At Northern Lights this year I saw three robots dead on the field, toward the end of matches, with main breaker trips due to overcurrent.
Yes. That is a real problem, and be sure that what you plug into a 30 amp slot doesn’t draw more than 30 amps (at least for any sustained amount of time). They’re thermal circuit breakers, so for short time periods(start-up), you can pull more than the number on them. The main breaker’s a thermal circuit breaker too.
But as long as you don’t run all your motors at once, especially near the end of the match, you should be fine for main breaker tripping and brownouts. Batteries also have limited energy stored in them, but that doesn’t become a huge issue unless the motors have lots of load on them and/or you are running many of them a great percentage of the time.
As I understand it, you also aren’t really running out of slots, just 40 amp slots. Good luck!