SAFETY WARNING: BEFORE PERFORMING ANY REPAIR TO WEB TECHNIQUES EQUIPMENT, YOU MUST TURN OFF THE POWER AND DISCONNECT THE EQUIPMENT FROM THE POWER SOURCE.
Machine Hits Preset A, Then Stops and Starts Again
- Need to adjust the "decel" pot on the motor control to be in the approximate range of the 10 o'clock position.
Machine Runs Wide-Open
- Is the main speed pot turned all the way up to maximum?
- Could be a bad main speed pot.
- Does the machine have a constant speed control? and is it turned on? and is it set to a high number?
- If the machine runs full speed and you can't control the speed, it is possibly a blown SCR on the motor control, then you would replace the motor control--they are not repairable--KB does not sell parts for them. Caution Warning, you need to find out what may have caused the motor control to fail in the first place. If you sell them a new motor control and they install it without repairing the problem that caused the first one to fail, it could blow the new motor control. Make them know that if they install it, they own it and they are responsible for testing to determine and repair the initial problem that caused the motor control to fail in the first place.
Machine Slows Down While Running
- Make sure that the machine didn't just hit Preset A, and is now running in idle mode (Can you adjust the speed with the idle speed pot?).
- Drive Belt Slipping, replace worn belt
- Check the Ice Cube relays on the main circuit to make sure they are pushed in all the way. Remove and replace the relays several times to make sure you are getting a good connection.
- Check for a loose connection on the back of the direction switch on the front panel, or replace the switch altogether.
- Could have a faulty main speed potentiometer; replace it with a new one (best to replace this pot & direction switch at the same time).
- Could be a bad reverser on the motor control, if so replace motor control (See Motor Control Testing).
Machine Won’t Run Full Speed
- Make sure that the machine isn’t just in idle mode. This is where the machine reaches Preset A (slowdown count) and idles until it reaches Preset B (stop count). See if they can adjust the speed with the idle speed pot, if so, check the presets.
- Bad Main Speed Pot
- Bad Direction Switch.
- Possibly they need to re-program the counter.
- Check to make sure the drive belt isn't worn and is slipping.
Machine Surges at Slow Speed
- The machine is surging at slow speeds because of the motor control trim pot called IR Comp.
- Use a very small Phillips head screwdriver, then locate and turn the IR Compensation potentiometer counterclockwise to stabilize the drive (prevent surging). Theoretically, turning the dial position to about a 9 to 10 o’clock setting should cure the surging problem, this is the typical setting we arrive at when we are testing the motor controls.
Machine Surges with Constant Speed Control On
Constant Speed Control Surges or is Erratic (OTHER THAN RUNNING TOO SLOW) For Constant Speed Controls PRIOR TO MAY, 2013 ONLY
- There is a possibility that this condition is caused by a bad reed switch that drives the constant speed control. On constant speed control machines prior to May, 2013, the constant speed control is driven by two reed switches 180 degrees apart underneath the counter drive roll. Now mind you there will also be two other switches that is used for length counting. The constant speed control switches are the ones two outer ones 180 degrees apart. The length counter switches are the two closest together.
- The symptom is that the constant speed control speeds up and slows down. This can be a slight change or up to mildly drastic. During this time the constant speed control never really reaches a constant speed and is like "hunting" for the correct target speed.
- The reasoning behind this is that perhaps is a "weak" reed switch that bounces a lot when the magnet comes near and engages it, but it continues to bounce. Bounce is when the switch goes to engage and it bounces against the contact creating and on-off-on-off situation.
- Diagnostic Tool: Unplug one of the switches and see if the constant speed control smoothes out. If not, re-plug that switch back on and un-plug the other one. If the second switch smoothes it out, then replace the first one or vice versa as the case may be.
- Recommendation: Replace both Reed Switches; always replace reed switches in pairs.
Machine Won’t Start
- Preset B has been reached, press stop button, reset counter
- Bad Main Speed Pot.
- Ice Cube Relays have wiggled out of their sockets, push them back in.
- Blown Fuses
- Loose connections/Break in the wiring
- Bad Direction Switch
- Jumpers on the main circuit board need checked to make sure they are not losing connection
- Motor Control is bad, perform motor control speed pot test and direction switch test
- Motor brushes have failed, replace brushes or replace motor.
Main Speed Pot is at Zero, Machine Still Moves
- Need to adjust the MIN Trim pot on the motor control, by turning it counterclockwise until the motor stops turning and “is quiet”.
Motor Starts Slow, Perhaps Needs Help to Start
- This indicates worn DC motor brushes, and the brushes may need replaced. However, this also indicates a worn armature. If new brushes do not cure the problem, replace the motor.
- Possible worn drive belt, check and replace if necessary.
- Need to adjust the ACCEL Trim pot on the motor control, by turning it counterclockwise until approximately 12:30 to 1 o’clock.
Main Speed Pot Won’t Slow Machine Down
- Is the machine in idle mode? If so, the main speed pot does not operate during idle mode, or only the idle speed pot.
- Switch to standby next to counter, if main speed pot doesn’t operate, replace the pot.
Stop Relay Engages
- The machine won't run, and the stop relay engages, then ask them if Preset B is set to zero. Preset B tells the machine to stop. If Preset B is set to zero then the machine won't run. It is possible the machine thinks it has reached the stop signal.
Machine Won’t Stop at Presets
If the machine won't stop at the presets, meaning it just keeps on running, a few things to check:
- First, make sure the Count/Bypass switch next to the counter is not on "Bypass Preset".
- Check the K2 Stop Relay to make sure it is plugged in all the way (remove and plug-in a couple of times). (If the machine does not go into idle mode, check the K3 decel relay make sure it is okay too).
- Make sure that the counter is respectively past these two presets in order to make them work for this next test.
If there is 115v between (Preset B output on back of counter) J2-2 and (Ground) J2-4, then preset A is good. If no idle mode then check for 115v between (Preset A output on back of counter) J2-3 and (Ground) J2-4. If both of these are good then check the wiring between K2 and K3 relays to see if there is a break. Or perhaps a bad K2 and/or K3 relay(s).
- Check the programming in the counter. If unable to correct the programming, then replace the counter.
- You can send along a new counter circuit board with the new counter for troubleshooting purposes. Sometimes customers may decide to keep the new one in order to have a spare. Remind customers that these repair ideas are not absolutes, but trial and error method.
Machine Only Runs One Direction
- Direction Switch needs replacing? Check to make sure that one of the wires has came off the back of the switch.
- Motor Control has a bad SCR (reversing module), if so, replace motor control (See Motor Control Testing).
Machine is Stuck in Idle Mode
- Relays in the counter could be stuck, replace counter.
- K3 Decel Relay is bad or loose or missing, (you can test this be swapping it with the K2 stop relay-they are the same relay)
- Bad Connection in the wiring harness from counter circuit board to main circuit board.
Machine Won’t Stop
- Possibly it is a bad motor control
- If you flip the direction switch while the machine is running, does it change directions, if not, possibly bad motor control or direction switch.
Machine Only Runs When Pressing (and holding) Green Start Button
- Chances are the K1 Relay has wiggled out of its socket enough to lose contact. Check the relays to make sure they are pushed in all the way. Check that wires are properly connected on the back of the Green pushbutton switch and on the main circuit board.
- Possibly wire #9 in the plug to the right of the K1 Run Relay may have lost connection. This wire runs from the green start button through the stop button to the connector next to the K1 relay on the main circuit board.