A dec 500 Dental Chair
A dec · Model 500 Dental Chair
Ultra-thin backrest that "flexes. Enables comfortable tuck of knees under the chairno hard metal back to worry about; cradles the patient in comfort and features upholstery thinner than 1" (25 mm) in some areas. Double-articulating, gliding headrest. Moves with the patient to improve comfort; adjusts easily with one hand. Innovative hydraulic lift system. Results in gentle stops and starts during patient positioning. Integrated 300-watt power supply. Provides more than enough power for the whole system; powers light and additional ancillary devices. Expanded height range. Offers a range from 13.5" (343 mm) to 31.5" (800 mm) so any doctor, regardless of height, can work comfortably. 60º swivel with brake. Allows 30º rotation on each side of center. Multi-position armrests. Rotates out of the way to streamline patient entry and exit/ Cut-away, cast iron baseplate. Allows you to roll your stool closer to the patient; provides six contact points for added stability on uneven floors.
Key tips
- ·Biological-indicator verification applies to dental sterilizers exactly the same as hospital CSSD - no exception for smaller units.
- ·"Sounds different" is often the first real report of handpiece bearing wear, not an outright failure - investigate early rather than waiting.
Typical Failure Modes
Compiled for this model from its own documentation and established engineering knowledge for this equipment class - not from a verified service record. Confirm against the manufacturer's service manual.
Motor / actuator / drive will not run or is weak
HighSymptoms: Traction force not applied, CPM carriage will not move or stalls, drive assist weak, motion one direction only.
Root cause: Worn drive motor / leadscrew / actuator, a hand-control fault, or a control-board fault.
Force / range / position inaccuracy
MediumSymptoms: Set traction force or CPM angle not reached, load cell drifts, carriage overshoots or stalls short.
Root cause: Load-cell / position-sensor drift, a potentiometer fault, or a limit-switch fault.
Hand control / patient-control fault
MediumSymptoms: Hand control unresponsive, the patient stop / reverse button does not work.
Root cause: Worn hand control or a damaged cable.
Frame / bearing / cable wear
MediumSymptoms: Rough or noisy travel, play in the carriage, frayed traction cord or rope.
Root cause: Worn bearings / slides or a frayed cable / cord.
Power / battery fault
LowSymptoms: Will not power on, short battery run time.
Root cause: Power supply / fuse or an aged battery.
Serviceable Parts & Consumables
Serviceable items for this model, compiled from its documentation and engineering knowledge for this equipment class. Service class and relative cost are estimates, not manufacturer figures; no part numbers are given. Confirm intervals and pricing against the manufacturer.
Drive motor / leadscrew / actuator
Class Major service partRel. cost $$$R&R Difficult
Load cell / position sensor / potentiometer
Class Major service partRel. cost $$R&R Moderate
Hand control
Class Periodic replacementRel. cost $$R&R Fairly easy
Bearings / slides / traction cord
Class Periodic replacementRel. cost $$R&R Moderate
Power supply / fuse / battery
Class Major service partRel. cost $R&R Moderate
| Part | Service class | Relative cost | R&R difficulty |
|---|---|---|---|
| Drive motor / leadscrew / actuator | Major service part | $$$ | Difficult |
| Load cell / position sensor / potentiometer | Major service part | $$ | Moderate |
| Hand control | Periodic replacement | $$ | Fairly easy |
| Bearings / slides / traction cord | Periodic replacement | $$ | Moderate |
| Power supply / fuse / battery | Major service part | $ | Moderate |
Relative cost: $ lowest · $$$$ highest service-part cost for this equipment class. Not a price.
PM Checklist
Preventive-maintenance tasks typical of this equipment class. Perform to the manufacturer's procedure and your facility's policy - this is general reference, not a schedule for this specific unit.
- ·Daily handpiece lubrication and autoclave cycle verification
- ·Compressor moisture-trap draining
- ·Annual full PM
Troubleshooting Approach
A starting sequence for this model, compiled from its documentation and engineering knowledge for this equipment class. Follow the manufacturer's service documentation for the actual procedure.
Symptom: Motor / actuator / drive will not run or is weak (traction, standing frame, powered rehab)
- Confirm mains / battery and that the patient stop / e-stop is released.
- Try the hand control and, if fitted, the unit buttons to isolate the control.
- Listen for the drive motor and check the leadscrew / cable / rope is not jammed or frayed.
- Check the hand-control cable for damage.
- Replace the hand control, drive motor or control board as isolated.
Symptom: Set force / range / position not reached (traction / CPM)
- Run the calibration / homing routine.
- Check the load cell / position sensor / potentiometer and the limit switches.
- Verify with a known weight (traction) or a goniometer (CPM / ROM).
- Replace the sensor if it drifts.
- Re-verify the range and confirm the patient stop works.
Symptom: Rough travel / play / frayed cord / worn bearings
- Inspect the bearings / slides and the traction cord / rope for wear.
- Check the leadscrew and nut for backlash.
- Re-lubricate per the manual.
- Replace worn bearings / slides / cord.
- Confirm smooth, quiet, safe operation.
Technical Specs
- Height
- 31.5
Typical Location
Where this class of equipment is typically deployed - general reference, not this unit's own placement record.
- Dental operatory
- Oral surgery suite
- CSSD (dental sterilizers)
Documents & Manuals
- A-dec 500 Delivery Systems Instructions for UseUser Manual · External
- A-dec 500 Dental Chair 12 O'Clock System Instructions for UseUser Manual · External
- A-dec 500 Dental Chair Owner's GuideUser Manual · External
- A-dec Model 551 Assistant's Instrumentation Owner's GuideUser Manual · External
- A-dec Preference ICC Instructions for UseUser Manual · External
- A-dec Preference Slimline Instructions for UseUser Manual · External
- A-dec Syringes Instructions for UseUser Manual · External
- A-dec Tooth Dryer Owner's GuideUser Manual · External
- A-dec/W&H EA-51LT Electric Motor Instructions for UseUser Manual · External
- A-dec 500 Dental Chair BrochureBrochure · External
- A-dec 500 Cuspidor Owner's ManualDocument · External
- A-dec Dental LightsDocument · External
- A-dec Self-Contained Water SystemsDocument · External
Troubleshoot this device with Bio
Describe a symptom or error code. Bio answers from this device's own documented error codes, failure modes, parts, and guides.
Ask Bio