Can this be done? I would like to have a variable speed control circuit for the motor on my canister filter. I want to slow down the flow without using the outlet valve as this makes the pump motor noisy. I'm not sure what kind of motor these filters use (ac, dc , brushless etc.). I was wondering if a light dimmer or ceiling fan speed controller would work. I just don't want the motor to overheat and burn up. Filter is a Penn Plaxx cascade 700. Any ideas are greatly appreciated.
canister filter speed control?
- Thread starter narkul
- Start date
I doubt it. They are running at the min power needed to pump the water. It may also damage the filter motor. Just stick with the output control.
That depends on the motor type.
"MOST small pumps use a SYNCHRONOUS MOTOR (a magnet as an armature inside a set of permanent windings in the case) These will only run at a givin frequency... in our case 60HZ. To change the speed you need to change the frequency. THIS IS THE ONLY WAY WITH A SYNCHROMOUS MOTOR. Any other attempt to change the speed (including friction) causes the motor to lose torque, stall, vibrate or overheat. Needless to say frequency drives are rather expensive. In other words the motor loses sync with the frequency. It however does not "slip" it just stops working. 1800 RPMS is the typical speed.
Most larger pumps use an INDUCTION MOTOR The armature has copper windings or a copper cage and IS NOT MAGNETIC. The field around the armature induces a voltage in it and cuases it to rotate. This type runs your furnace, tablesaw, ampmaster pump, etc. The rotation "slips" behind the frequency... this 1740 rpms is the common speed. You can get this kind of motor to slip farther behind...you do lose torque and generate a lot of heat. A frequency drive works best here also.
An SHADED POLE motor is an induction motor and typically has several sets of windings. The speed can be varied by applying different currents to the different sets of poles. This is where the singled ended or AUTOTRANSFORMER comes into play. These are found in some furnace motors, bathroom fans etc. You can usually spot these motors as a stack of plates that look like a transformer with the armature in the middle. These speed controls cause a loss of torque but fair better with capacitance or choke based controll.
A UNIVERSAL MOTOR is one that uses brushes. These can be speed controlled by simply adjusting the voltage. RHEOSTATS or VARIACS are commonly used. The universal motor is not efficient and has more wear parts. Your drill, is an example of a universal motor."
-bean on RC.
"MOST small pumps use a SYNCHRONOUS MOTOR (a magnet as an armature inside a set of permanent windings in the case) These will only run at a givin frequency... in our case 60HZ. To change the speed you need to change the frequency. THIS IS THE ONLY WAY WITH A SYNCHROMOUS MOTOR. Any other attempt to change the speed (including friction) causes the motor to lose torque, stall, vibrate or overheat. Needless to say frequency drives are rather expensive. In other words the motor loses sync with the frequency. It however does not "slip" it just stops working. 1800 RPMS is the typical speed.
Most larger pumps use an INDUCTION MOTOR The armature has copper windings or a copper cage and IS NOT MAGNETIC. The field around the armature induces a voltage in it and cuases it to rotate. This type runs your furnace, tablesaw, ampmaster pump, etc. The rotation "slips" behind the frequency... this 1740 rpms is the common speed. You can get this kind of motor to slip farther behind...you do lose torque and generate a lot of heat. A frequency drive works best here also.
An SHADED POLE motor is an induction motor and typically has several sets of windings. The speed can be varied by applying different currents to the different sets of poles. This is where the singled ended or AUTOTRANSFORMER comes into play. These are found in some furnace motors, bathroom fans etc. You can usually spot these motors as a stack of plates that look like a transformer with the armature in the middle. These speed controls cause a loss of torque but fair better with capacitance or choke based controll.
A UNIVERSAL MOTOR is one that uses brushes. These can be speed controlled by simply adjusting the voltage. RHEOSTATS or VARIACS are commonly used. The universal motor is not efficient and has more wear parts. Your drill, is an example of a universal motor."
-bean on RC.
Great info. It sounds like a synchronous motor controller is probably too expensive. Might it be possible to make a bypass by putting tee fittings on the intake and output lines and joining the two with a valve. Adjusting the valve opening would regulate the amount of water that can bypass.