Pureteenlard wrote:
> I need to know because my speed controller is rated well above 15 amps
> but if I overvolt my 180w motors to 18v will the current rise too or
> just the power?
There are basically two items you need to focus on: Voltage and Heat.
The FETs used in the ESC have a maximum voltage rating and a maximum
amount of heat they can dissipate per unit time. They usually don't
tell you the heat rating directly, instead they tell you the amount of
power (voltage times amps) it can deliver to the motor. (They take the
efficiency of the ESC design into account and usually tell you what size
heat sink is needed or the amount of air in CFM to maintain the maximum
continuous power output.)
You should *NOT* exceed the maximum voltage rating without expecting it
to fail because the parts being used simply can't handle it. For
example, an ESC designed for an R/C car may have a maximum voltage of
12v and a power rating of 500 watts. In that case, even if you are well
below the power rating, you may still blow the ESC if you trying pushing
18v through it.
You *CAN* exceed the maximum power rating if you use a large cooling
system (e.g., bigger heat sink, more fans, liquid cooling, etc). The
added cooling removes the excess heat and allows the FETs to operate a
bigger load without failing. Strictly speaking, the higher operating
temperatures and loads will in fact reduce the overall lifetime of the
FETs, but for our purposes (operating a couple dozen hours per year)
that's not a major problem.
Frank P.
--~--~---------~--~----~------------~-------~--~----~
You are currently subscribed to the "R/C Tank Combat" group.
To post a message, send email to [email protected]
To unsubscribe, send email to [email protected]
Visit the group at http://groups.google.com/group/rctankcombat
-~----------~----~----~----~------~----~------~--~---
