Pro Planer speed control box problem

[charlese]

[quote="tdubnik"]When I try to bridge the gaps on the board per Eds suggestion]

I would recommend stranded wire given a twist. Solder will adhere, but will also interlock into stranded wire - giving a more secure hold.

Your soldering technique should start with tinning - (heating the wire only and getting solder to run into and between the wire's strands) Then it will be a lot easier to connect the solder filled wire to the solder post on/in the board.

Solder has little tensile strength (only forms continuity) and needs some interlocking to adhere. Solid wire does not give this feature. That is precisely the reason we run into so may "cold solder" joints. If when the bottom of a board is subjected to a splash of solder, one of the component's arms is not heated enough a weak joint is formed - called a cold solder joint. The arching of current through the small broken opening between the component and the board causes extreme heat and is often what causes failure of board, or component.

In the "Old Days" before printed circuits, we always tied knots in wires prior to soldering.

Back on the subject of size of wire. I would recommend using small stranded wire of the same size as the components connectors. This is a small gauge.

For the record - I favor connections as illustrated in Ed's post #32

[reible]

Thanks for the pictures!

This looks like a very simple design.

If the repair doesn't work one might be able to do a work around using one of the speed control boxes they sell for routers connected to a bridge to go to DC. I think those come with either a 15A or 20A rating which I'm guessing is way beyond the requirements here. A lamp dimmer as I recall is not good for too much power, 600W or so? But perhaps they have larger ones?

Anyone see a problem with this idea?

I haven't seen anyone giving us output voltages to the feed motor but those would be interesting numbers to know...

Ed

[tdubnik]

Thanks for the pictures!

I haven't seen anyone giving us output voltages to the feed motor but those would be interesting numbers to know...

Ed

The notation on the motor indicates 115V and 6 amps. It is a 1/20 HP motor rated for 3300 RPM. Whether the motor is rated this way or actually uses that much power; I don't really know.

I obviously can't measure the actual output range to the motor since my board doesn't work at the moment.

[tdubnik]

Back on the subject of size of wire. I would recommend using small stranded wire of the same size as the components connectors. This is a small gauge.

For the record - I favor connections as illustrated in Ed's post #32

Well, I tried. I bridged the gaps using the diagram from Ed. I used the soldering techniques as described by charlese. I then traced the area between the foil where I made my connections with an X-acto knife to make sure there wern't any unintentional bridges. I checked and rechecked and everything looked good. I connected the power and the wire bridging the long gap promptly burned out.

Is it possible too much power is getting to the board from the rectifer?

[johnm]

Well, I tried. I bridged the gaps using the diagram from Ed. I used the soldering techniques as described by charlese. I then traced the area between the foil where I made my connections with an X-acto knife to make sure there wern't any unintentional bridges. I checked and rechecked and everything looked good. I connected the power and the wire bridging the long gap promptly burned out.

Is it possible too much power is getting to the board from the rectifer?

It sounds like a short in the feed drive motor or in the connections going to the motor.

[reible]

Hi,

Sorry I didn't mean you could measure but rather someone who has a working one.

Given the motor numbers it is as someone mentioned a higher voltage motor. Maybe on of the EE's can help refresh my memory but it seems to me the bridge output at 115 means a sinewave input of 115/1.41 or about 80 volts AC. However I think that only works for sine waves and the output of the AC circuit will be some sort of chopped version, still the rms of that still needs to yield that voltage???

Anyway that seems to be do-able with the router controller idea. One would have to use a meter and start lower then work your way up to the 115V then use some sort of physical block to keep the dial from going any farther (if any remaining rotation is possible).

This is a very interesting post. Thanks for sharing!

Ed


[quote="tdubnik"]The notation on the motor indicates 115V and 6 amps. It is a 1/20 HP motor rated for 3300 RPM. Whether the motor is rated this way or actually uses that much power]

[Ed in Tampa]

Well, I tried. I bridged the gaps using the diagram from Ed. I used the soldering techniques as described by charlese. I then traced the area between the foil where I made my connections with an X-acto knife to make sure there wern't any unintentional bridges. I checked and rechecked and everything looked good. I connected the power and the wire bridging the long gap promptly burned out.

Is it possible too much power is getting to the board from the rectifer?

tdubnik
I thought you said the motor worked? If so make sure there are no shorts in the the connection going to it. Check the input to the board it should be dc and I'm guessing 50 volts or less.
If the input is good and the connection to the motor are good and there is no shorts in that mess, and the motor works then it is my guess the coil is shorted drawing to much power and burning up the bridge.


Okay we know the motor is DC 50 volts and 6 amps. I still think a model train transformer/controler would work just fine. I would plug it into a power strip and wire its output to the DC motor. Then I would put a plug on the wire coming from the planner motor and plug them into the power strip. Now the switch on the power switch would control all power to the planner. You could easily adjust the feed rate using the throttle control on the train transformer/controler. That would be the fastest and dirtiest way to fix this problem.
Ed

[johnm]

Thanks for the pictures!

This looks like a very simple design.

If the repair doesn't work one might be able to do a work around using one of the speed control boxes they sell for routers connected to a bridge to go to DC. I think those come with either a 15A or 20A rating which I'm guessing is way beyond the requirements here. A lamp dimmer as I recall is not good for too much power, 600W or so? But perhaps they have larger ones?

Anyone see a problem with this idea?

I haven't seen anyone giving us output voltages to the feed motor but those would be interesting numbers to know...

Ed

Interesting idea! Harbor Freight has router controllers for $15; for that price, I suspect it's a big lamp dimmer. If the feed motor can handle the chopped up AC from a lamp dimmer, it might work.

[tdubnik]

tdubnik
I thought you said the motor worked? If so make sure there are no shorts in the the connection going to it. Check the input to the board it should be dc and I'm guessing 50 volts or less.
If the input is good and the connection to the motor are good and there is no shorts in that mess, and the motor works then it is my guess the coil is shorted drawing to much power and burning up the bridge.


Okay we know the motor is DC 50 volts and 6 amps. I still think a model train transformer/controler would work just fine. I would plug it into a power strip and wire its output to the DC motor. Then I would put a plug on the wire coming from the planner motor and plug them into the power strip. Now the switch on the power switch would control all power to the planner. You could easily adjust the feed rate using the throttle control on the train transformer/controler. That would be the fastest and dirtiest way to fix this problem.
Ed

Ed when I connected the power neither motor was plugged in. When I measure the pwoer going INTO the board from the rectifer it measures 115V AC. I guess this means the rectifer is bad?

[johnm]

Hi,

Sorry I didn't mean you could measure but rather someone who has a working one.

Given the motor numbers it is as someone mentioned a higher voltage motor. Maybe on of the EE's can help refresh my memory but it seems to me the bridge output at 115 means a sinewave input of 115/1.41 or about 80 volts AC. However I think that only works for sine waves and the output of the AC circuit will be some sort of chopped version, still the rms of that still needs to yield that voltage???

Anyway that seems to be do-able with the router controller idea. One would have to use a meter and start lower then work your way up to the 115V then use some sort of physical block to keep the dial from going any farther (if any remaining rotation is possible).

This is a very interesting post. Thanks for sharing!

Ed

The 115V on the AC side is RMS, so the DC out of the rectifier should peak at 115*1.414 = 160 V.