641 Chair Power To the Table models w/ Rotational Base Troubleshooting

Model

 641 -004 and -005
Serial Number All

This illustration shows only the components that affect all table functions. Refer to the following page for a detailed description of the power supply to the table.

641 Power to table

•If Power Light is off, there is no power to PC Board. If Power Light is On, proper voltage is present at PC Board.

•Black and white wires supply 48-54 VAC to power circuitry for the Base and Back actuators.

•Red and orange wires supply 34-37 VAC to power circuitry for the Tilt and Foot actuators, hand/foot controls, power light, all limit switches, and position sensors.

With the table's power cord properly connected, facility supply voltage (115 or 230 VAC) is supplied thru the cord to the power inlet.

Equipment Alert

The voltage setting displayed in the power inlet window must match facility supply voltage (115 or 230 VAC). Remove fuse holder and rotate 180° to change voltage setting.

Current flows from the power inlet thru the EMI filter board, then back thru the power inlet fuses to the rotational base PC board.

641 Power to the table

Current flows thru the rotational base PC board to the main system transformer. The transformer reduces the voltage and current flows back to the rotational base PC board.

Circuitry on the rotational base PC board provides the required voltage to power the rotational base brake system. The reduced voltage is supplied to the main PC board thru the rotational base PC board.

This transformer is protected from overload by a thermal cutout feature. This will automatically reset when the transformer cools.

Line voltage (115 or 230 VAC) is supplied to the main system transformer thru the rotational base PC board. The transformer reduces the voltage and current flows back to the rotational base PC board, then to the main PC board thru two separate windings - four wires.

The black and white wires supply 48-54 VAC to power circuitry for the Base and Back actuators only. The red and orange wires supply 34-37 VAC to power circuitry for the Tilt and Foot actuators, hand/ foot controls, power light, all limit switches, and position sensors - on Midmark models only.

When voltage is applied to the PC board, the power light is illuminated.

Circuitry on the PC board provides the required voltage to power all of the table's components: hand/foot controls, actuators, limit switches, and position sensors.

Circuitry on the main PC board supplies 8-10 VAC to the hand / foot control connection ports.