TREADMILL TIPS
BELT LOSES POWER
This condition is when the treadmill operates
normally without a person on the belt and then slows down when someone steps on
the belt or when the treadmill operates normally for a given period of time
with someone on the belt then abruptly begins to slow down.
There are four typical causes for this problem (listed
in order of our experience:
1) The walking belt and/or deck are worn. (85%
of the time)
2) The walking belt and/or motor belt are too
tight- if you have adjusted either recently. (8% of the time)
3) The
motor has lost torque and needs brushes or has demagnetized or has developed
high resistance. (5% of the time)
4) The controller is dropping output. (2% of the
time)
Walking Belt is Worn:
The only certain way to test for a worn walking belt is to take a
DC amp draw (if you have a DC treadmill) or an AC draw (for AC). Trying to look
at the belt or a feel test is highly unreliable. Better tests, if you lack a DC
ammeter (they are expensive for a good one), are a coast test or an incline
test. To test the deck, go back to the Troubleshooting section and download the
belt and deck inspection instructions. The coast test is to get on the
treadmill as the lowest incline setting and walk on the treadmill at 3 MPH.
Pull the safety key and it should take you 2-3 full steps to stop (this is a
general rule…some like a few Tunturi models stop on a dime even with a healthy
belt but for most models, this tests works well upon). Fewer steps indicate
high friction. The incline test is to put the treadmill at max incline and walk
on it at 3 MPH. If the treadmill operates normally at max incline but bogs down
at minimum incline, replace the walking belt. Gravity takes over for the drive
system eliminating much of the friction problem. On some heavily worn walking
belts, this test will not eliminate the problem.
Walking Belt/Motor Belt too Tight:
If you have adjusted the walking belt or motor belt recently,
check for this problem. When the belts start slipping, some people just crank
down the belts and on treadmills, tighter is not necessarily better. The
tighter the belts, the more the drive system has to work to keep everything
moving. You should be able to lift the walking belt (with the treadmill
unplugged) in the center of the treadmill about 2-3” without straining. Tighter
belts should be loosen but make sure you don’t create a dangerous slipping
situation by loosening.
The motor belt (with the treadmill unplugged)
should be able to be turned by hand to almost a 90 degree angle from its normal
operating position. Loosen the belt if too tight. Make sure to test for
slipping and if it does with the proper tension, replace the motor belt.
Needs Brushes / Demagnetized Motor /
Resistance Problem:
Typically when we find a motor that
has lost torque; it needs a new set of motor brushes. Typically we can make
brushes for almost any motor if we don’t already stock them. Motor
demagnetization is not that common but it does happen and it is normally easy
to diagnose. If you have confirmed the belt and/or deck is not worn and the
belts aren’t too tight, you can test for a motor torque problem. DO NOT USE
YOUR HAND OR ANY OTHER BODY PART TO IMPEDE THE MOTOR…YOU WILL LIKELY LOSE YOUR
BODY PART IN THE PROCESS IF THE MOTOR IS GOOD. The step to test for the motor
is to use a foreign object preferably on a long shaft. First determine the
direction of the motor spin (most have directional movement printed on the
motor tag), then apply pressure with an object with downward pressure on the
flywheel in the direction the flywheel is turning (do not attempt to put force
against the rotating direction of the flywheel as you can easily injure
yourself). If you can slow the motor, typically you need brush replacement. To test for demagnetization, the motor must be
disassembled. Once you have the motor retaining bolts removed, remove the motor
core by sliding it out of the end of the housing. If the magnets pull the core
against the housing and it is difficult to remove, the magnets are good. If the
magnets do not attract the core, the motor has to be replaced. To test for high
resistance on DC motors, you must use a multi-meter for accurate testing. Put a
test lead in the positive lead (usually red) and the other in the negative lead
(usually black) and then set the meter to the ohms scale. Readings that are
normal are between 1 and 2. Some small motors will have higher readings and
larger motors have lower readings. Readings above the normal range indicate you
have high resistance in the motor and we have seen them incredibly high. Since
the copper flexes every time it energizes, the ability of the windings to
conduct electricity is reduced over time. Large motors typically are more cost
efficient to have rewound. Smaller motors are typically cheaper to replace.
Controller:
This is the most uncommon of the causes. Typically replacing a controller
in this situation will not solve the underlying problem and then you will end
up replacing a belt as well as a control. Normally if a control is dropping
output, it will do it with a person on the belt or not. Tests of DC output
dropping is normal in many controls since they have a current limiter which
will automatically drop output to prevent burning up the board. This is best
diagnosed by eliminating the other possible problems first. If you are left
with the control as the cause, replace the control.
Walking Belt Friction Problems
As the
walking belt wears, it creates more friction with the deck which creates more
heat in the belt causing it to wear further. Additionally, the increased
friction requires the motor to work harder to keep the belt moving at the same
speed. With this in mind, it causes the motor to draw more electricity and
therefore, more power to move the belt.
The motor has to get rid of this excess
energy in some way so the way it normally does it is by releasing it in heat so
that's why treadmills with belt problems typically overheat the motor too. All
of this to say that if the breaker starts tripping, you know that the belt is
causing the motor to pull too many amps and the safety system is working as it
should. If the breaker has tripped more than a few times, it will need to be
replaced because the breaker weakens every time it trips. Additionally, the
walking belt will need to be lubricated at a minimum and if you want to be very
aggressive toward the symptoms, replace the walking belt.
WHY USE TREADMILL BELT CLEANER?
If your
treadmill is properly maintained, you should not have to clean the backing of
the belt, unless it is in a normally dirty area (we recommend that you keep
your treadmill out of these areas). What you must do to the backing of the belt
is lubricate it. We have formulated a lubricant (World Famous Treadmill Lube)
that has an agent that actually repels dirt from the underside of the belt. It
also has another agent that has a high heat constant which means it takes more
energy to heat it up (that keeps the heat lower). So, if you keep it maintained
(cleaning, etc.) and lubricated, you shouldn't have a problem with dirt on the
underside of the belt. To understand why to use belt cleaner, you first have to
understand the dynamics of a conveyor belt driven system. Most home treadmills
have a DC controller attached to a DC motor which is belt driven to a front roller
which is a belt driven conveyor system. Walking or running on this conveyor
system creates heat (from the friction of the belt backing). If you have too
little friction, the treadmill will not operate properly (the most evident
problem is on an incline the treadmill will keep speeding up). The energy
exchange process creates heat.
The pressure that is exerted against this system
from the user, for the average person, equals hundreds of thousands lbs. of
pressure every mile. In other words, no matter what the lubricity of the belt
is, the potential for heat build up is great. If you combine this with a nice
layer of dirt on the top of the belt (acting as an insulator) your heat
constant will certainly rise. Removing the dirt layer from the top of the belt
helps reduce belt heat and thereby lowers the amp draw requirements of the DC
electrical system. This helps the controller and motor run cooler in addition
to the heat level of the belt. We have tested treadmills before and after belt
cleaning and have seen a 20% reduction in the amp draw of the unit. This could
be a major contributor to the longevity of the
1) motor brushes 2) armature of the motor 3) DC motor controller.
1) motor brushes 2) armature of the motor 3) DC motor controller.
