3.
Which of the following procedures applies to removing and replacing a faulty base
motor when the chair is in the UP position?
a. Place a block of wood between the pantograph arms on one side and lower
the pantograph slightly to grip the block of wood securely.
b. After you have reconnected all of the electrical leads in the junction box and
reconnected the power source, run the motor clockwise until it stops to
correspond with the raised condition of the lift.
c.
Leave at least one inch of space remaining between the parallel pantograph
arms when the motor stops at the low lift position because the lift must not
over travel when the pantograph arms close up under power.
d. Once the lift is at the lower extreme position, adjust the height of the lift.
Loosen the locknut on the adjusting screw and turn clockwise to lower the
lower limit of the lift.
4.
Which of the following is a true statement about changing a base motor when the
dental chair is in the DOWN position?
a. You do not need to remove the chair as you do when the chair is in the UP
position.
b. You must always replace the chain when you replace the motor.
c.
You must be sure the limit switch cover is secure before you slide the gear
motor forward.
d. You will need a helper to lift up on the lift assembly while you remove the
faulty motor.
MD0373
3-21