Can anyone tell me how many magnets go on the driveshaft and the best way to attach them and where?
Richard
Richard,
Mine were held on with the tie wraps that came in the kit. There were two magnets for balance. I always had reservations about them slipping and wanted to add epoxy or double sided stick tape. Been there many years Amigo and no problemo. Put your energy and money somewhere else as this is simple.....zzzzzzzip. all done
HTH,
John
Thanks John,
That's the way I had installed them, but they didn't stay. I might try a dab of epoxy and see if that works. I installed the Rostra unit about 4 or 5 years ago and could not get it to work. I now have the time to get it going so here goes.
Richard
Hi
I sell Rostra Cruise Controls
see--> http://good-times.webshots.com/photo/2844340100037964197ZHEGrI
The Rostra requires a minimum of 2000 pulses per mile and a maximum of 38600 pulses per mile
<>The average bus tire turns approx 500 revolutions per mile -
<> with a 4.10 rear end ration the drive shaft turns 4.10 times per as fast as the tranny output shaft
<> you also need to factor in the tranny overdrive (if applicable) - example the Allison V730/V731 tranny third gears is .88 to 1
so
<> (500 tire revs / mile) X (4.10 rear end ratio) then divide by .88 (tranny overdrive factor) = 2050 / .88 = 2329.5
<> and usings the minimum # of magnets to evenly be spaced on a driveshaft (that's 2) = 2329.5 x 2 ==== 4659 pulses / mile
so -- 2 (TWO) EVENLY SPACED MAGNETS - and the Rostra Switches set to 4000
Pete RTS/Daytona
Sorry about hi- jacking your thread Richard but I think you got your answer.... I have a question for Pete looks like your kit mounts to the air throttle pedal is that correct? Other than the magnets on the drive shaft and the pick up everything is in the coach? I just need to supply the 40 odd feet of wire to connect the two. Am I seeing right?? I have a stone bennet harness to install this spring I may as well install the cruise control harness. Seems Like a reasonable price for the kit. Thanks for posting.
Paso One
Yep - The Rostra Global Cruise Control Typically mounts "all up front" - pulls the throttle pedal - even simplier if you have a front wheel speedo pulser (they will connect directly to the Rostra - if there is at least 4 studs on the front wheel hub)
I've simplified the Rostra Install Instructions down to just a few wire connections
<> 12V Ignition Power (+)
<> Ground (-)
<> Speed sense wire
<> 12V stop light wire (@ brake Pedal) - If yours are 24Volt - no worries - I supply a free 24v relay to do the interface
<> then just mount your switch and plug it's connector into the main unit
<> set the setup switches (I provide a comprehensive switch setting guide for Bus Conversions) and your done
Pete RTS/Daytona
And for those who are wondering, ours drives the mechanical throttle cable all the way to it's limits without problems.
We had an electrical problem, but it came from the turn signal switch. Ours is a break before make and the stoplight circuit wants a make before break switch. We added a light bulb by connecting it between the stoplight switch wire and ground, and that eliminated the problem.
Occaisionally, we get some strong electrical interference that shuts the unit off. We haven't found the source, yet, but it doesn't happen often.
For what it's worth.
Tom Caffrey
I chose to install separate clutch and brake switches - partly to keep it all separate from the 24V system, but partly because of the delay in the air-pressure switch used in my brake system. I prefer to be able to disengage the unit with a touch of the brake pedal rather than a positive application that the pressure switch needs.
I've got a VDO speedo operated off a hall-effect sender on the output of the gearbox and the signal from that drives the cruise control OK.
Oh, and don't believe Pete about including a 24v relay. Sometimes he forgets. ;-)))
Tony Lee
Your sooo right - My Rostra Inventory was low and I had your unit sent directly from the warehouse - so the 24 volt relay that I was suppose to put inside your box - never got inside your package - PLEASE send me an Email and re-confirm your shipping addy and I will send you your relay
Tom Caffrey
I'll send you my lastest installation HINTS & TIPS - it will tell you which UNUSED wires can cause a noise problem
Pete RTS/Daytona
Yes, I could see the reason for no relay Pete. No big deal and I was just having a dig at you. We do have such things here in Oz and they are hardly big bucks to buy
Actually yesterday was the first time I have been able to fire it up because the bus was sitting for three months and then it wouldn't work because I had been concerned at the interface between the 24V pulses from the VDO system and used a resistive divider to reduce the voltage. Turned out that the VDO speedo fed 12V to the pulse generator rather than 24 v so I had been overcautious and the unit wasn't getting a valid speed pulse to work with.
Only problem now is the up switch may be a bit dickey, but because Tasmania is a small place with no straight roads where I am now, I can't get a decent chance to test it properly. Maybe tomorrow.
PVCCES Exactly where did you put the light ,I am having the same problem.
Buspit, you don't have the kind of coach listed in your profile, so I'll try to make allowances for that.
In our coach, power is supplied directly to the stop light switch. This means that if I hit the brake treadle with the master switch off, the stoplights come on.
The wire downstream of the stoplight switch feeds into the turn signal switch. If the turn signal switch is in the center position, both stoplights light up. If the turn signal switch is turned either direction, this disconnects one of the turn signal lights and reconnects it to the flasher output.
There is a very short time when switching that the circuit is open, which causes the Rostra to think that the stoplight circuit has a broken wire. This is what makes it turn off.
We connected an ordinary trouble light to the wire running between the stoplight switch and the turn signal switch. We connected it's other lead to ground and left it turned on.
This provides a fairly low resistance path to ground while switching the turn signal so the Rostra continues to have a stoplight load while being switched. The trouble light lights up anytime the stoplight operates, but this doesn't seem to cause any problem.
However, there is one thing to check. Our GM coaches have a load sensing relay that turns on the dash stoplight indicator when there is enough load to be two lamps burning. It is not supposed to make the indicator light up if one bulb burns out.
You should make sure that the lamp or resister does not fool the relay when one lamp is removed. I believe that it is just a matter of experimenting with the load to get the result that you want.
Good luck with your fix.
Tom Caffrey
The Rostra is unique in the way it senses the brake switch. The Rostra VIOLET brake sense wire (cold side of the brake switch) MUST see a very low resistance and 0 volts to continue in cruse control mode. When the brake switch is pressed the Rostra senses the 12 volt and drops cruise control but also ANYTHING OTHER than the normally low resistance of a standard type stop lamp resistance will Cause the Rostra to drop cruise control.
Unique turn signal circuits that interrupt the low resistance stop light or LED replacement stop lights will cause problems for the Rostra.
To fix the LED / high resistance problem - Wire a FIVE pin 12v cube relay to let the violet wire see ground during NON Braking and lose ground (Float) when the brake is applied
Relay pin 85 to cold brake (+12v when brake applied) -
pin 86 & pin 30 to ground -
pin 87A to Violet wire - pin 87 not used
(for 24 volt brakes - Use a 24 volt cube relay & wire pin 85 to the cold brake +24v)
Pete RTS/Daytona
Pete said -"Tom Caffrey
I'll send you my lastest installation HINTS & TIPS - it will tell you which UNUSED wires can cause a noise problem "
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Now that I'm back on the mainland with decent (relatively) roads, I've had a chance to try my unit out.
I'm still having a problem with getting it to engage when the R/A button is pushed. Sometimes it works and other times it doesn't and then it will engage seemingly several seconds after I last 'fiddled" with the buttons.
Once it engages it is perfectly stable and speed can be raised and lowered reliably using the two buttons. Just getting it to kick in in the first place is the problem and I can't work out the set of conditions that are causing it so I can pin it down..
Obviously some sort of interference could be causing it so could you send those instructions so I can check if i missed anything. I have got the clutch and brake switches set fairly finely, but if it was them, I would expect it to drop out when hitting bumps and that is not the case.
Thanks
Tony
I added the relay for my brake light input as shown by Pete. I installed the relay about 4 inches from the Rostra Conntrol module. With only the wire from the brakes lights and a ground connected to the relay coil (terminals 85 & 86), everytime the brakes were released, the cruise control would turn on??? No wires from the relay to the control module???
Here is what I found: when the brakes were released, the magnetic field created by the coil in the relay would collapse, producing an "electrical charge thingy"(I think it is called EMFI). The relay was close enough to the Rostra Control module to trigger the module causing it to turn on. Problem solved by adding a diode across the coil terminals (85 & 86) on the relay. Jack
"The relay was close enough to the Rostra Control module to trigger the module causing it to turn on. Problem solved by adding a diode across the coil terminals (85 & 86) on the relay. Jack"
Yes, it's always been good practice to add a resistor or diode across coils. Stops a lot of sparking at the switch contacts and reduces EMI.
Having the cruise control is good - I can practice my tap dancing moves while cruising down the highway.