DMHC Controller Tech Sheet

[kudos]

I have just received a kit from MacmotorTech that comes with a DMHC controller.

It looks like it's this:

http://www.e-dmhc.com/product?id=10



It's tiny for an 18fet controller!

I can't find any tech sheet for it, so I don't know what the max voltage is, I want to use my 52V battery so 58Vish fully charged.

Anyone know?

 

[DanGT86]

Based on that sticker it looks like the Low Voltage Cutoff point is 42v. A common pack of 14 lithium ion cells in series would be 3v per cell at 42v. That is a nice safe cutoff point to consider the pack "empty".

I think its safe to say that controller is made for a 14s 52v pack which is sometimes referred to as 48v. Lucky for you that is exactly what you have. :thumb:

 

[kudos]

Hey Dan, thanks for your input on this, I was thinking along the same lines as you.

I do have both 12S and 14s packs available so I think I'll try the 12S first which will be around 50V fully charged.

I'll see what options are available on the display to see if there is an option for a 52V battery.

I did ask and get a response from MacmotorTech but it wasn't very useful:

-----------------------
48V is our standard setting.

You can try the display for adjusting to 58V. If not, you can send it back that we program
-----------------------

I have also reached out to DMHC directly to see if they have a tech sheet.

 

[DanGT86]

Yeah the low voltage cut of 40v is going to be pretty high for your 12s pack though. The fact that they told you you can change it at the display is a clue that the voltage wont hurt it.

This looks like a nice compact controller. Isn't this the same folks that make the Fardriver controllers? Is the software the same for changing settings?

 

[kudos]

OK so I powered up for the first time and the display unit was already set to 52V battery.

Having said that I’m not sure exactly what was and what wasn’t configured by MacmotorTech.

I found a manual online because of course there is zero information with the kit.

When I go into settings, the controller was set to max amp of 15A ! So that has been changed to 40A.

Time has been set by me, I wouldn’t expect them to have set this of course.

Wheel size is set correctly 26”.

What I’m unsure of is the ‘Poles in motor’ option, it’s currently set to 6 and ‘Start after poles’ set to 3.

I haven’t built the wheel up yet so the motor is just in some upside forks for testing, it seems to run fine when I use the throttle.

When I check online the Mac Motor has 32 magnets with 16 pair poles, so I’m not sure how this relates to the number six poles in motor that is set - any ideas?

 

[DanGT86]

Generally poles is asking about magnetic pole pairs. So 16 magnets are 8 pole pairs. If the controller knows how many pole pairs you have then it knows what the motor rpm is. In your case with 16 magnets the hall sensors will all trigger 8 times per full revolution of motor.

If the controller is using this for speed on your display and its a geared motor or a chain drive then the speed will still be incorrect since one revolution of motor doesnt equal one revolution of wheel.

Im thinking 3 poles to start means it wont start from a completely dead stop but I'm totally guessing on that.

If it spins the motor properly then the poles setting is probably just for the speedometer.

 

[E-HP]

OK so I powered up for the first time and the display unit was already set to 52V battery.

Having said that I’m not sure exactly what was and what wasn’t configured by MacmotorTech.

I found a manual online because of course there is zero information with the kit.

The kits on the MacmotorTech website have controllers using JST connectors, not the Higo/Julet connectors from the controller on your link. Does the Mac motor have a single connector too (3 large pins and 6 small ones)? If they are part of a kit and they made sure the parts are compatible, then if the motor is geared, it should be expected to have a speed sensor in the motor, with one of the wires in the HIGO/Julet that sends the speed signal to the controller.

 

[kudos]

The website has the old kits on show but they have this new kit with the Hugo Juliette connectors now too which isn’t online yet.

The unloaded max speed is showing as 32mph, which seems about right considering the wind I requested 10T and the voltage I tested at 50.2V.

 

[E-HP]

The website has the old kits on show but they have this new kit with the Hugo Juliette connectors now too which isn’t online yet.

The unloaded max speed is showing as 32mph, which seems about right considering the wind I requested 10T and the voltage I tested at 50.2V.

Is it still registering the speed while the wheel is coasting down to a stop? If so, seems good.