Two beeps from Magic Controller

[Just]

Hi all,

I have a Magic Controller (48V, external), which was used for Pie-II motor.

When I connect a power to the controller, it issues 2 beeps.. It issues these two beeps with no matter either a Throttle or Motor are connected.
I did the following tests:
1) Throttle is connected, Motor is disconnected - the Controller issues 2 beeps when it gets connected to the power (48V)
2) Throttle is disconnected, Motor is connected - the Controller issues 2 beeps when it gets connected to the power (48V)
3) Throttle is disconnected, Motor is disconnected - the Controller issues 2 beeps when it gets connected to the power (48V)
4) Throttle is connected, Motor is connected - the Controller issues 2 beeps when it gets connected to the power (48V)

I checked the throttle - it works as expected. I checked the Motor - it also seems to be in a work condition. I replaced the battery - a result remains the same.

So, where is a problem - in Controller? How the Controller should be tested? How can I be sure that the Controller is not functional (till now it was just my suspicion)?

Actually I have an USB cable to program the Controller. So, if I success to program it, does it mean it's in a workable condition?

Please advise.

Thank you

[truly_bent]

Have you checked that the hand brake signals to the controller are closed? If you haven't wired your handbrakes to the controller (using handbrake levers with the switch built in for example), it's likely you have to jumper out the handbrake inputs to the controller. Otherwise your controller sees a break in the line as a request to coast the motor, or go into regen mode.

Just a guess.

Jeff

(Edit: I confess I haven't checked the polarity if the brake signal. The schematic I found at the GM site only shows a image of brake levers, not whether they're wired NO or NC. My presumption is that they're connected NC)

[Just]

Thank you truly_bent for your comments!

"Have you checked that the hand brake signals to the controller are closed" - it's currently disconnected (floated).
"you have to jumper out the handbrake inputs to the controller" - where to connected? to 'Z'(GND) pin in the controller's connector?

BTW, if I short  between the 'GND' pin on the Motor Connector and and 'Z' pin on the Throttle/Brakes/Crouse/... Connector, the Controller stops issuing the beeps and overall system starts working :-)

So, here is one more tip, which was not described previously (at least I have not found it in the forum) - it might be helpful to connect between 'GND' and 'Z' pins in the Front Panel of the Controller.

Anyway, is there a reason for leaving the Battery's GND and the overall system GND (Controller's 'Z' pin) floated one regarding another?

Thank you

[Bikemad]

BTW, if I short  between the 'GND' pin on the Motor Connector and and 'Z' pin on the Throttle/Brakes/Crouse/... Connector, the Controller stops issuing the beeps and overall system starts working :-)

So, here is one more tip, which was not described previously (at least I have found it in the forum) - it might be helpful to connect between 'GND' and 'Z' pins in the Front Panel of the Controller.

Anyway, is there a reason for leaving the Battery's GND and the overall system GND (Controller's 'Z' pin) floated one regarding another?

Dmitryl, the "GND", "0V" and "Z" pins should all be connected via a common ground track inside the controller. If one of the pins had a poor soldered joint, or the ground connection to the hall sensors 0V contact has been damaged, it would explain why you were getting the two beeps which indicates a hall sensor fault.

Anyway, it's good to hear you've got it sorted.

The schematic I found at the GM site only shows an image of brake levers, not whether they're wired NO or NC. My presumption is that they're connected NC

Jeff, your presumption is partially correct as the spring loaded switches are in fact NC (normally closed), but as the switch contacts are only able to close when the brake lever is pulled, they tend to spend the majority of the time with their contacts held open by the brake lever return spring.
So it is probably much easier to understand their operation if you simply consider them to be Normally Open switches in this particular application.

When the brake levers are activated the switch contacts will close, creating a closed circuit on the brake switch wiring from the controller, which disables the throttle and engages regen.

Alan
 

[Just]

'NC' normally states for "not connected" :-(

[truly_bent]

Sorry for the confusion. When looking at switch contacts. NO refers to Normally Open while NC is Normally Closed. You're right that NC also means Not Connected, but not in this instance.
J

[Morgen 3Eman]

On my MP3, the grounding of a  brake input pin caused the motor to go into Regen mode. 

And it sure sounds like you have a broken ground string.

TTFN,
Dennis