EZGO Electric Tachometer

[JohnnieB]

Originally Posted by kgsc

Very interesting... JohnnieB, did you have the sensor connected to the controller at the time?

Yes, J5 was plugged into controller.
Had to be or the PDS controller (Curtis 1206MX) would have gone into limp mode.

J5 Pin-1 (Black wire) is B-
J5 Pin-2 (White wire) is Sensor output (Pulses)
J5 Pin-3 (Red wire) is B+ (~14V)

If you have an aftermarket controller that doesn't use the speed soenor (like an DCX), you need to power the sensor. 12V will work and you'll need a pull-up resistor (~2K).

Here are the sensor specs on my D&D motor.

[JohnnieB]

Originally Posted by yurtle

I don't think Alltrax uses this sensor.

Originally Posted by sportcoupe

JohnnyB has an Alltrax DCX, no speed sensor input needed.

My DCX controller does not use a speed sensor, but my D&D motor has one, so I'll be feeding it 12V from a DC to DC converter.

I'm pretty sure the output from a motor speed sensor can also be used to feed some of the electronic speedometers instead of pulses from the frame mounted sensor and wheel mounted magnet they normally use. The trick is getting a speedometer that can be adjusted to a small enough tire diameter.

[rbuggies48IN]

I have a series cart so no speed sensor. Still investigating/getting an education on stuff I don't know about series motors and possible tachometer. I messed with a bike type speedometer before I went to gps speedometer - I found the bike magnet set-up on that system difficult to fine tune/adapt to cart so jumped on gps speedometer when it came out. Therefore not real interested in changing a bike unit into an RPM equivalent. Thanks to all for the great insight, knowledge and feedback!!

[INWO]

I may be offering a kit for Gem cars
It also fits Tomberlin.
Is this 3 wire plug standard to others?
If not it can be hard wired.
It will use an optically isolated input to eliminate any common ground issues.
5 digit led, programmable for motor rpm or cart speed.

Piggy backs on existing hall effect sensor.

[Volt_Ampere]

Great idea. I could care less what my motor RPM is but using motor RPM to calculate and display MPH is great! I am working on my own unit to do this along with a Time, Temperature, Odometer. Speed, Odometer will be off of the speed sensor optically coupled. Compute will be with an Arduino. I am still debating the display. Most displays are hard to read in the bright sunlight.

[rbuggies48IN]

My Speedhut GPS Speedometer. Lots of design options & easy install.

[JohnnieB]

Originally Posted by rbuggies48IN

My Speedhut GPS Speedometer. Lots of design options & easy install.

It's blasphemous to have a Bar-graph type battery meter surrounded by Cadillac bling.

[INWO]

Originally Posted by INWO

I may be offering a kit for Gem cars
It also fits Tomberlin.
Is this 3 wire plug standard to others?
If not it can be hard wired.
It will use an optically isolated input to eliminate any common ground issues.
5 digit led, programmable for motor rpm or cart speed.

Piggy backs on existing hall effect sensor.

Here is my interface circuit.
If someone uses it, give me some feedback.
Works great for me.
A user told me that his controller blacks out when ever he touches wires or checks with vom.

I believe he has other issues, as 1k ohm isn't going to load circuit.

Led counter is programmable to any pulse count. Power from 12v converter.
The blue and yellow go to neg and signal tach leads.

I wonder if most need the harness, It adds a lot of work to the project.

[JohnnieB]

What is the max PPS (Pulse Per Second) input the programmable counter will operate at?

For example, when the speed sensor on my motor is putting out 27,976 PPS, can it be programmed to display 28.5 (MPH) or 6,994 (RPM)?

[INWO]

Originally Posted by JohnnieB

What is the max PPS (Pulse Per Second) input the programmable counter will operate at?

For example, when the speed sensor on my motor is putting out 27,976 PPS, can it be programmed to display 28.5 (MPH) or 6,994 (RPM)?

Theoretical 100,000 pps.
Divided by 99,999 maximum.

So roughly:
Set to read pps (can be set to pps or ppm)
Divide by 1000 (or any number)
Would read 27.976

Interface may not respond fast enough.
May not be needed if meter is powered from same source as sensor.