Why does my motor make a strange sound when it starts up?
The RampStart switch frequency is approximately 100Hz which is in the audible spectrum. This was selected so that the ramp operation can be validated by listening to it when it is switched on.
Can I use this to drive my motor in reverse as well ?
The RampStart is designed to sink current in ONE direction only. However, by using one relay downstream to do the direction changing, and another to remove the power from the RamStart (upstream) during the switch over, then re-applying power you can do this.
Why does the motor I have connected to the RampStart keep re-starting and won’t get to full speed?
If you power the RampStart from the same source as your load you must ensure that the voltage does not drop below 5.0v or the on-board brown-out protection will activate and re-set the RampStart. This phenomenon may only be visible with the aid of an oscilloscope.
Why does my pump keep re-starting when my solenoid activates ?
The RampStart has a built in low voltage detection and will automatically re-start if the supply voltage drops below 5.0v even briefly. It is likely that your bulk power supply cannot deal with the current drawn by the solenoid while your pump is running. You may need to upgrade your power supply, or, for a better resolution to this issue, consider using a RampStart on your solenoid.
Why is there no difference in the speed that my motor starts? It is the same with or without the RampStart.
Please check the connections to the RampStart module are correct. The return wire for your motor must go to the RampStart “Ls” pad, not to ground.
Why does my motor start up at top speed? I have checked the connections between my motor and the RampStart and they are correct.
If the RampStart “Ls” pad is connected directly to the power supply at turn on then the driver circuit will fail in short mode. Remove the RampStart from your system and measure continuity between the “Ls: pad and ground. It should be an open circuit.
Can I connect RampStart modules in parallel to increase the current handling capability?
No. To handle higher current loads correctly you should use a driver transistor coupled to the “Ls” pad. The RampStart is a current sink, therefore you must consider this when adding your transistor.
When my halogen lamp blew it “popped” is this because of the RampStart, how come?
Halogen lamps have a higher internal gas pressure than ordinary lamps, they also run at much higher temperatures. Because of this they are made from fused quartz which is sensitive to the oils in human skin. By touching the lamp with bare skin it can cause hot spots which will can crack, causing the lamp to explode. The RampStart will actually increase the life of tungsten filament lamps because they generally fail at turn on when the filament is cold an brittle. The RampStart allows the filament to warm up and settle before coming up to full temperature.