Can a pwm dc fan speed be controlled with a voltage controller connected ONLY to neg. & pos. wires?

I have a 9HV1248P1H001 - Sanyo Denki 48v DC PWM fan and, being noisy at max speed, I wanted to vary the speed using a PWM motor controller
(PSM-244 DC 10-60VDC PWM Motor Speed Controller With Housing - 10A)
which has only a two-wire output for ground and power. The fan will be installed on a fume extracting application.
According to Sanyo Denki specs, the acceptable applying voltage to the fan is 36V to 60V.
Can I only connect 2 wires from the fan to the controller? Is it safe for the fan?
I’d appreciate your professional advise.
Thank you!


Welcome back to our community, I am going to ask out team and get back to you.

That would be great. Thanks!

Results can vary in this sort of context.

Controllers of the type referenced are best suited for old-school brushed DC motors, and function on the principle of turning the power to the controlled device on & off at a rapid rate.

Nearly all small DC fans these days use brushless motors however, which depend on electronic devices to sense the rotor position and time application of the supply voltage to the motor coils appropriately. It’s hard for those devices to operate properly if somebody’s constantly turning the lights on & off…

While direct PWM of the power supply can be used for controlling brushless fan & there are ICs designed to do just that, it’s not generally recommended by fan manufacturers and those ICs generally operate at low frequencies on the order of 10s of Hz–enough to let the electronics get a few proper commutation cycles in every time the lights come on. The referenced controller operates at 25 kHz, which I’d expect to cause problems if used directly.

That said, one could filter the output of said controller to end up with something approximating a variable DC supply. An L-C using a AIAP-03-101K and ECA-1JM222 might be a reasonable starting point.

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Thanks for your advise Rick!
However, I dont want to modify the controller.

Can this controller be used “as is” with a 3 wire fan (ground-power-sense) such as
Sunon XGC0384BX-1000U-A9H?

The point was to avoid buying the expensive Sanyo Denki PWM fan controller
If that was the case (no less expensive choice available) which of these SD controllers would be the right choice for the 9HV1248P1H001:



Modification of the controller itself was not the suggestion, so much as putting a few parts in between it and the powered device.

The XGC0384BX-1000U-A9H appears to be a 2-wire device, so no difference with the original material in question.

“3-wire” fans are typically one of three things:

  1. A fan that allows speed control via a logic-level (input) signal
  2. A fan that facilitates numeric measurement of speed through a logic level (output) signal
  3. A fan that gives a yes/no indication as to whether it has be hit by the #*%& and thus stopped completely, again via a logic level (output) signal.

The three controllers linked in your prior post appear designed to interface to the type (1) above, and unsuitable for control of 2-wire devices.

This post speaks to related topics, and may be of useful information.

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Thanks for replying,
I’m sorry maybe I wasn’t precise on the above post.

The question about the three controllers (SD), I listed there consisted on which one among them would be more suitable to use (manually controlling the fan speed being the main criterion) with the Sanyo Denki HV1248P1H001 fan (pwm dc fan) which I have it already.

Meanwhile, the Sunon XGC0384BX-1000U-A9 - yes you’re correct, it is a 2 wire dc fan Sunon_XGC0384BX_1000U_A9H.pdf (306.1 KB) - I brought it up as a possible purchase option to use it with the simple controller already in my possession, in order to avoid buying one of the expensive Sanyo Denki PWM controllers listed above.


Hmm. Somehow missed that the fan in question had a control input…

All three of the Sanyo controllers would be suitable for controlling devices with low-level control inputs; the bare types expect differing input mechanisms (e.g. voltage vs resistance) depending on part number and the enclosed unit comes with it’s own knob and (obviously) enclosure. Additional features are included also, which are part of the cost.

As for using the first-referenced controller as a signal source for driving a low-level input, that’d be overkill by a factor of about 5000, but perhaps workable. I’m finding no info on the maximum input voltage permitted for your fan’s PWM input however, and though it’s not uncommon for them to tolerate connection to the fan’s own supply, I’d not trust that convention at 48V. Depending on the output structure of the controller (e.g. high- vs. low-side switch) one might go about the matter in different ways.

One could also toss together a 555-based circuit for a few bucks and save the controller for something more appropriate, or switch a simple resistor inline for two-speed operation, or go about the matter in a few other different ways.

Thanks for the input!
What about the alternative aforementioned Sunon fan (2pin and DC voltage variation 36V-60V )?
Would you theoretically say that it might be suitable to be used with my existing controller 10V-60V( as is?



Based on the information that driver/controller provides I would think it would work for that fan (XGC0384BX-1000U-A9H).
So far I did not see information in the documents for that fan how it will handle being driver that way. But, also it did not say it cannot at all.

Further reading if found. I would recommend looking over it in case I overlooked any relevant information.

Thanks for your suggestion!