by jonathannc » Wed Oct 28, 2009 8:48 pm
Hi all.
I'm a pretty new member here. therefore don't know how much other members know. one thing I do know I know very little compared to some.
that said i have messed around with SCR's, control systems electric motors to some degree.
These motors as you probable know are series motors as such operate on AC or DC.
Using SCR for control is great however for safety reason towards over voltage as in your case 240 volt to 120 v motor would factor in a safety margin .
setting the trigger threshold " limit the SCR firing angle" the SCR will limit an over voltage event from accruing so to speak. great for running a 120 volt motor on 240
you could also limit the variable resistor range of travel and achieve the same result.
running two 120 volt series motors on 240 volts in series is doable. however, if one of the windings shorts out on one motor the other motor will fail due to over voltage .
you could overcomplicated the system .for every motor have a feed back circuit controlling each scr for every motor installed if a motor started to show signs of pending failure would trigger the feed back circuit and power down the offending motor.
one thing I noticed when looking up your motor is the rated Average Life for 115923 its 500 hrs , that's like 2 hrs a day 5 days a week for a year or 2 hrs a week for 5 years. averages hay..