Simple digital tachometer

[volp]

I was looking for a Tachometer for my B6001 with a D950 engine. The engine got a fitting for a mechanical tachometer but a suitable meter was expensive.
The digital tachometers on Ebay were inexpensive. I bought one with sensor for about 13 dollar.
First I fixed the magnet on the front pulley with epoxy.
The sensor was fixed to the frame.
The tachometer was mounted in a plastic box on the top of the dashboard.
The wiring is straightforward.
What is important is that the magnet is mounted with the correct pole towards the sensor! Try first by moving the magnet back and forth in front of the sensor with power connected. If you get no reaction it is the wrong pole and you have to turn it around. I missed that and had to remove the magnet by force and mount a new one!
You can see a simple digital voltmeter below on the dashboard. I think this is more useful than an ampere meter.


Anders

 

[D2Cat]

That's a nice set up with good visibility.

Tiny Tach has a unit that has a clamp that goes on the injector line and functions off of the pulses from the IP.

 

[ShaunBlake]

I was looking for a Tachometer for my B6001...
The digital tachometers on Ebay were inexpensive. I bought one with sensor for about 13 dollar...

You can see a simple digital voltmeter below on the dashboard. I think this is more useful than an ampere meter.

Anders

Oh boy! I've been thinking my next upgrade would be a tach, and you've provided the inspiration for a volt meter as well! Your timing is impeccable!

 

[volp]

The sensor also have a red LED which flashes when the magnet passes when power is on. So you do not have to watch the meter when you fine tune the position of the sensor.

Anders

 

[Diydave]

Excellent, cheap solution! I mounted a calc-an- acre sprayer monitor to many a lawnmower, that way...

 

[85Hokie]

Is this what you got?

http://www.ebay.com/itm/Tachometer-...0&pid=100005&rk=2&rkt=6&sd=281551016414&rt=nc

almost too good to be true!

 

[Dieselbob]

After reading your post I was looking at these, my only concern is how susceptable they would be to water. With the BX dash, there are limited places to mount it where it would be protected. I found ALL KINDS of whatproof inductive gas engine tachs, but I couldn't find a single waterproof Hall effect tach.

 

[volp]

Is this what you got?

http://www.ebay.com/itm/Tachometer-...0&pid=100005&rk=2&rkt=6&sd=281551016414&rt=nc

almost too good to be true!

Spot on!

Anders

 

[volp]

After reading your post I was looking at these, my only concern is how susceptable they would be to water. With the BX dash, there are limited places to mount it where it would be protected. I found ALL KINDS of whatproof inductive gas engine tachs, but I couldn't find a single waterproof Hall effect tach.

Only time will tell how susceptible to water this is.
If you wanted further protection you could glue a small visor on the housing.

Anders

 

[kubotasam]

How close does the magnet need to be to the sensor?

 

[85Hokie]

How close does the magnet need to be to the sensor?

somewhere I read .....

Power requirementC 12/24V
Measure range : 5-9999RPM.
Clear zero: Automatic.
Clear zero time:about 10s.the greater the RPM value,the longer the clear zero time.
Refresh frequency: 0.2-0.5S@120-1200RPM;0.25-0.06S@2400-9999RPM.
Measure indication:RPM<5000,±2;RPM>5000,±3.
Display:RED 0.56” LED
Signusle signal,Hall NPN 3 wires normally open.
Hall proximity model:NJK-5002C
Appearance:M12mm cylinder.
Detection range: 10mm
Proximity output current: 200mA
Detected objects: magnet
Response frequency: 100HZ
Tachometer dimension:72x36x20mm,panel cutout Dimension:68x33mm.
Sensor dimention: M12x10x55mm.
Sensor wiring:brown-Power+;blue-Power-;black-signal.
Operating temperature: 0 to 50°C.

 

[volp]

How close does the magnet need to be to the sensor?

Less than 10 mm (0.39 inch).
I have 3-4 mm.

Anders

 

[Dieselbob]

OK, I got one of these and am ready to install. One question. On the three wire plug that goes into the back of the readout panel, I'm ASSUMING that the black signal wire from the sensor goes to yellow wire label "IN". Correct? I don't want to fry it right off the bat.

 

[volp]

OK, I got one of these and am ready to install. One question. On the three wire plug that goes into the back of the readout panel, I'm ASSUMING that the black signal wire from the sensor goes to yellow wire label "IN". Correct? I don't want to fry it right off the bat.

Black is IN!
(Sensor wiring:brown-Power+; blue-Power-; black-signal.)

Anders

 

[ShaunRH]

Might be interesting to rig one of these to the PTO shaft so I can see true RPM's off the shaft.

 

[ShaunBlake]

Might be interesting to rig one of these to the PTO shaft so I can see true RPM's off the shaft.

That would work; great idea! hmmm... how to mount...

 

[phantomgeo]

I was wondering do you need to worry about throwing the flywheel out of balance?

 

[Diydave]

I was wondering do you need to worry about throwing the flywheel out of balance?

Not on a relatively slow moving diesel crank. If you were concerned, you could always glue a similar non magnetic weight 180 degrees on the other side.

With regard to the PTO mount, usually there is an inch of unused shaft, forward of the PTO coupler. You would just have to be careful on hookup, to not knock off the magnet...

 

[volp]

I have noticed a slight problem with the RPM display. It can be difficult to read i sunlight.
Thinking of making a shade of neoprene and glue it to the display.

Anders

 

[Dan_R_42]

That's a nice set up with good visibility.

Tiny Tach has a unit that has a clamp that goes on the injector line and functions off of the pulses from the IP.

Has anyone installed a Tiny Tach on a B7100 ? Wondering about a location to mount the display.

http://www.tinytach.com/diesel.php