625 Table Back Function Components Test and Repair

625 Table Back Function Components

This illustration shows the back limit switches, the serviceable components of the back actuator, and the fuses on the main PC board. Use the table below to isolate the malfunction.

Problem

Required Action

Motor does not run.

Check main PC board fuses: F1, F2, F3, and F4

Perform Limit Switch Test below.

Back function operates, but makes grinding / squeaking noises

Clean / lube actuator threads.

Replace actuator if necessary.*

Motor runs, but table does not move.

Inspect / replace motor coupler.*

*Replacement instructions are provided with the part. They are also available on midmark.com.

625 Table Limit Switch Test

1.Disconnect wires from switch.

2.Place meter probes on COM and NC terminals.

Check switch Tripped and Untripped.

With Switch Untripped

Meter Reading

Required Action

OL

Replace limit switch

less than 5 ohms

Limit switch - OK

Perform PC Board Test below.
With Switch Tripped

Meter Reading

Required Action

OL

Limit switch - OK

Perform PC Board Test below.

less than 5 ohms

 Replace limit switch

625 Table PC Board Test

Equipment Alert

The base limit switches will not stop movement during this test. Do not run past max. / min. positions.

1.Move Base section so that it did is approximately half way between its maximum and minimum positions.

2.Tag, then disconnect back and base actuator wire connections at J4 and J5. Tag then disconnect back and base sensor wire connections at J6 and J7.

Equipment Alert

Failure to move both connections may result in damage to PC Board.

3.Move back actuator connection to J5 and back sensor connection to J6.

4.Using the hand / foot control, press and hold Base Up briefly, then, press and hold BASE down briefly.

5.Calibrate PC Board.

Did Back move up and down in Step 4?

Required Action

Yes

Replace main PC board*

No

Refer to: Back Actuator Motor Resistance Test

*Replacement instructions are provided with the part. They are also available on midmark.com.