SPEED ON DELTA 31-396

First, remember any electric motor whether it is rated at 500 rpm's or even 10,000 rpm's you can always change the rate of speed the part it drives without changing the speed of the motor simply by changing the size of the pulleys, drums or gearbox ratio. Meaning I can take the 500-rpm motor and drive something at 100 rpm's or even at 3,000 rpm's as long as it can handle the load. In turn the same applies to the 10,000 rpm motor I can drive something with it at 5 rpm's or 50,000 rpm's at the same time as the motor continues to run at 10,000 rpm's though keeping in mind the heavier the load the more horse power you would need.

However, it does not always mean you should because most machines have been designed by engineers to run at the optimal rate for the purpose for which it was designed and in most cases, it is not advisable to exceed the equipments rated speed limit and by doing so can cause serious injury, mutilation or even de@th.
With that said and since you did not say if you want to speed it up or slow it down you will either increase or decrease the size of the drum or pulleys by ¼", ½", ¾", and so forth up or down by x-amount inches to obtain the desired rate of speed (RPM'S) for which is being driven. In this case, the sanding belt unfortunately changing the size of drums to the belt may not be an option.

Second option would be to put a control knob on it similar to a dimmer switch for the lights in a home where you can adjust how much power the motor receives. Nevertheless, if you plan to do this there are factors that should be taken into consideration because you do not want to override any safety features "nor" if the motor is not designed to run at a slower rate it could cause it to overheat and burn your motor up. Other thing is the switch must be able to handle the current (110, 220, or 440) you plan to run trough it otherwise you would melt it and possibly get a serious shock killing anyone using it. Meaning a typical dimmer switch will be hazardous to your health and you must use one designed for the purpose you intend to use it for in this case a 220 powered motor. Remember the volts are not what kill's you it is the amp's and higher the volts the higher the amp's and it only takes 100mA to stop your heart.

Other options is to rewire the motor because in most cases pending the motor it can be rewired in three different ways slow, medium, and fast simply take a look at the plate on the motor with the wiring diagram on it to determine if this is possible. It is advised if you do not know how to perform electrical work best to get a pro.

Final and perhaps the best option would be to replace the motor in similar size, rpm, spindle, volt; etc except you would change it out for a variable speed motor and a power control switch but do not exceed the speed limit keep it within the spec's, and slowing it down x-amount should not cause any harm.

Just always, use caution when mucking around with such things and yes, in most circumstances you can always change the speed of something with just a little money and know how but always think safety first.

Billy from Hayward CA.

Hi, Please don't shoot the messenger, but the answer to your question is, no. The 396 has a 3 horse 220vac single phase motor and no speed control.


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