Hi all,
Can someone tell me please - What is the maximum motor volts I can use on a Motor Shield? And why?
Searching around has not come up with a definitive answer.
The datasheet says that with the "Vin" jumper disconnected, the max Vin voltage is 18V. Why is this?
The L298 H-bridge chip is rated at 46V, and looking at the shield schematic, there are 8 x SS14 quench diodes
rated at 40V, and 3 x 10uF caps across the input, rated at 35V. So why the 18V limit?
Is it because 'best practice' says that one shouldnt run the caps at more than half their rated value?
If so, why not give us higher rated caps so that we can utilise the full capability of the L298...
I need to drive some 12V,1A latching solenoids (these need polarity reversal to change state, hence the Motor Driver)
on the end of a LONG cable, so I need to supply something like 30V at the Driver end to make up for the drop across
the L298 and the cable.
10uF caps across the input, rated at 35V. So why the 18V limit?
Is it because 'best practice' says that one shouldnt run the caps at more than half their rated value?
Probably yes. Electrolytics can fail in a 'dramatic' fashion. Their lifespan definitely falls rapidly as you approach their max rating.
Thanks for pointers and opinions.
Since I'm using this shield with Vin disconnected from Vmot, and I'm just driving solenoids,
I dont see why I need the ripple-suppression 10uF caps at all, so I think I'll just remove them,
along with their 18V working limit, which should mean I can then go up to 35-40V, should it not?