[GRAH1]

Ive just taken delivery of a truespeed controller from Steve Hills and I must say a very nice job it is too .When I contacted Steve about this controller earlier this year I explained that I always use a thumb controll and Steves were based on trigger type handles .Steve offered to build one into a thumb handle for me so I sent an SCD rythm stick handle down and Steve made a custom wiper board to suit .The advantage of a controller such as this is that basicaly you have a setting to suit every occasion , recently I have found that when using motors such as the moto gp a "normal" transistor controll can be a little to touchy and to combat this I added an extra adjustment to give several more steps to compensate .However with Steves Controller it is posible to tune the acceleration curve and also reduce the motor power to make the thing more drivable there is also a sensitivity controll which is like reducing or increasing the ohms on a normal controller .The brakes have two adjustments one for amount of braking and one for the time the brake is applied the way this works is the brakes come on and then after a preset time they are released alowing the car to roll on into the bend giving the driver time to get back onto the power for the exit .
The whole package is very well engineered and will handle 31 amps which should be enough for most set ups .The controller comes with the owners name printed on the case so no picking the wrong one up on a club night which has happened to a couple of our members .
At £177.50 it is probably one of the most expensive things you will probably purchase but I should point out that a controller of this quality will last a long time ,I have had my previous controller for 20 yrs and I expect this one will last easily as long making it cost a touch over £8.00 a year so when put into perspective its not expensive .I plan to test it on friday at John Ps proxy round so with the variety of motors in the cars it should get a good evaluation but my early feelings are that its an item well worth having .
Nice one Steve

 

[Slotracing Al]

QUOTE (GRAH1 @ 18 Jul 2007, 20:37) <{POST_SNAPBACK}>The whole package is very well engineered and will handle 31 amps which should be enough for most set ups .
Yeh 31 amps should be plenty for a hot slot car motor.
But what happens when there is a short circuit - where the current can easily exceed 31 amps?
Transistor failure occurs on quite a few other makes of transistorised controller for exactly this reason. Does this one have some sort of protection against excess current?

 

[gecko]

I've had a Truspeed controller for a couple of months, and in my opinion it has totally changed my racing (for the better!!). The best money I have spent in a long time, excellent stuff.

Cheers,

Mark

 

[RichD]

A well designed controller would have a fuse or circuit breaker to protect the transistor in the event of a short. Tracks should have a fuse or circuit breaker for each lane, 30 amps could easily burn up your track wiring unless it is 10 gauge.

 

[GRAH1]

Perhaps Steve can answer the question about short protection as I havent seen his circuit diagram but I would be surprised if he hasnt built any protection into the circuit as the rest of the package is very well engineered

 

[Chris Frost]

QUOTE (RichD @ 20 Jul 2007, 01:54) <{POST_SNAPBACK}>A well designed controller would have a fuse or circuit breaker to protect the transistor in the event of a short. Tracks should have a fuse or circuit breaker for each lane, 30 amps could easily burn up your track wiring unless it is 10 gauge.

Unfortunately fuses or circuit breakers cannot be relied upon to protect transistors.
I've helped lots of people replace transistors that have failed in circuits that do have protection by fuses or circuit breakers.
The problem is that transistors can fail quicker than the fuses or circuit breakers can operate.

Some sort of over current protection such as fuses or circuit breakers are a good idea. They will limit other damage after a transistor has failed and sometimes (but not always) protect the transistor from failure.

Chris

 

[Steve Hills]

Hi all,
thanks for your comments and the opportunity to reply to questions.

Thanks Graham for the initial posting and your remarks. I have heard that you're one of the clever guys out there, so it means a great deal to me to have your approval.

Chris answered perfectly the problem of fuses trying to protect output devices such as transistors or Mosfets.
He is quite correct that the fuse is more to halt additional damage than to prevent it in the first place.
My income is generated from the repair if music related electronics goods where the output stages are blown, and the fuses then blow to prevent fires etc.

Since the PWM controller is designed to work with both 1/24th and 1/32nd scale racing, one value of fuse cannot fit all the variations in power draw needs.
The 1/24th guys usually have 'power relays' connected as close to the plug terminals as possible to reduce the fractions or a volt lost along the wiring, so I decided that since a fuse looses the same, it would be best to leave the over-current issue to be dealt with in the club track wiring as RichD suggests, and not within the controller. That way the club PSU is protected with a specific fuse for its own ratings, and the controllers are free from that impossible task.
What I have done in the design is to make replacement of the output devices an easy job in case there is a damaging over-current or wrong connection situation.

I hope that covers the question, but please feel free to quiz more.

regards to all,
Steve Hills.

 

[GRAH1]

Thanks for the reply steve ,I gave the controller a good test tonight and Im pleased to say it performed very well especialy when used with a car which was quite difficult to drive .The use of the power reduction control and the acceleration tamed the difficult car enabling the available power to be used to maximum effect .Hopefully I can give it a further test at pendle on tues day before I return to Crete .

 

[Steve Hills]

QUOTE (GRAH1 @ 21 Jul 2007, 01:09) <{POST_SNAPBACK}>Thanks for the reply steve ,I gave the controller a good test tonight and Im pleased to say it performed very well especialy when used with a car which was quite difficult to drive .The use of the power reduction control and the acceleration tamed the difficult car enabling the available power to be used to maximum effect .Hopefully I can give it a further test at pendle on tues day before I return to Crete .

Hi Graham,
I forgot to mention that the RELEASE function is not just a pure timer, but works in conjunction with the motor speed.
It is a timer coupled in with the motor speed feedback so that if you are going too fast for the brakes to release at the setting you've chosen, they stay on till you've slowed down to the correct speed.
The function explanation that I send out with these controllers may need a little revision to make that easier to understand.

Have a great time in Crete.

regards,
Steve

 

[GRAH1]

Steve the controller made the trip to crete ok and arrived safe and sound now all I have to do is build a track on the patio to use it on