Ultra Chair Base Potentiometer Test and Repair
Base Potentiometer
If necessary, base positioning potentiometer, Item 1, can be over-ridden in order to operate Base section. While holding down Program button on membrane or foot switch, press desired Base directional button.
Unplug chair power cord before removing covers or working on chair. Failure to comply could result in personal injury.
Removal
1.After positioning chair, unplug chair power cord and remove Covers.
Use caution to prevent electrical shock with chair plugged into outlet. Electrical components and connections are exposed.
2.Disconnect plug connector, Item 4, from Base Potentiometer Assembly, Item 1.
3.Remove Base Potentiometer Assembly (Item 1), by removing two mounting screws, Item 2, and one washer, Item 3.
Installation
1.Position Base Potentiometer Assembly, Item 1, onto chair and secure with two mounting screws, Item 2, and one washer, Item 3.
2.Connect plug connector, Item 4, to Base Potentiometer Assembly, Item 1.
Adjustment
Place chair at its lowest position before performing adjustment procedures.
Base Potentiometer - 2
1.Loosen mounting screws on Base Potentiometer Assembly Item 1, and rotate assembly so pinion gear, Item 2, is disengaged from drive gear, Item 3.
2.Rotate pinion gear, Item 2, on potentiometer shaft counter-clockwise (A), viewed from back of potentiometer, until it stops, aligning teeth on pinion with teeth on drive gear, Item 3.
3.Turn the pinion gear, Item 2, back, (clockwise) two teeth and align with drive gear, Item 3.
4.Rotate Base Potentiometer Assembly so pinion gear, Item 2, is engaged with drive gear, Item 3. Tighten mounting screws.
5.Unplug chair power cord. Place SW1 switches, Item 4, on PC board, both in On position.
6.Plug in chair power cord. Press Calibration button, Item 5.
Chair automatically completes two cycles during Calibration. First cycle finds the extreme end of travel sensor settings. Second cycle checks to assure settings have been stored and can be recalled by software.
7.Unplug chair power cord. Place SW1 switches, Item 4, to desired operating position. Refer to: SW1 Switch Settings.
8.Plug in chair power cord, and check Base Up and Base Down positions using directional buttons on foot or membrane switch.
Base Up and Down positions should almost reach maximum travel. If necessary, readjust potentiometer.
9.Install Covers.
