Wiring Diagrams & Layouts

UNITEC offers both Otis and Esco original contract wiring diagrams and layouts. Our Otis documents and archives go back to early 1900’s

Wiring Diagrams

When requesting a wiring diagram be sure to provide your wiring diagram number, this number is located at the bottom of your controller data tag.

What you need to know about wiring diagrams:

  • Wiring diagrams are schematics used to troubleshoot the electrical systems of the car controller, door operator, fixtures and machine.
  • Otis wiring diagrams are typically broken down by numbered areas; main power distribution, door operator, car and hall fixtures to name just a few.
  • The standard for Otis wiring diagrams is that they be drawn with the car at 2nd landing, doors closed and main-line disconnect off.  There are many exceptions to this case, so be aware of your unit’s specific wiring.
  • Having a set of wiring diagrams on the job site is critical to making timely repairs in the case of an issue or shutdown.

Wiring Diagram Protector Document

Wiring Diagrams and Layouts Product Sheet


When requesting a layout be sure to provide your sales or job number which is located near the top of your controller data tag, be careful not to confuse the sales number with the serial number,  UNITEC does not use the serial number in any instance. The sales number can also be found on the crosshead.

What you may find in a layout includes:

  • Building Reaction Loading figures
  • Crucial loading data: DUTY, Overbalance, Sheave Shaft Load, Safety Load, Counterweight mass, Car mass
    • Numerous elevators have had local (not necessarily approved) changes, Cab Mods, weight additions or change.
    • Enabling the confirmation of loading is crucial to safe elevator turn over
  • Machine type, Governor type, Safety type, Ropes Qty-Size & Type/Break strength (COMP, HOIST GOV.), Sheave Diameters
  • Drive Sheave Groove type and traction type
  • Door system specifics such as: Opening sizes, types and qty-making it easier to estimate equipment
  • Approximate installation dates in order to estimate which CODE conditions were accounted for at time of installation
  • Buffer Qty, Free Length and Stroke -actual loading
  • For Hydros:
    • Permits the accurate estimating data for building new jacks or Hydro Power units-limiting the need for time consuming surveys
    • Piston Diameter, length, Wall thickness, Hole depth, Cylinder diameter, Jack type –(Holed, Holeless, Dual or Single, Roped or not, Telescopic or not)
    • Tank unit Hand & capacity.
    • Hydro Motor HP, Pump Gallons per Minute, Site Voltage

*Please note that the documents provided by UNITEC in connection with wiring diagrams and layouts reflect the intended conditions of the equipment at the time of installation. Actual current conditions may not be reflected in these documents due to changes that occurred at the time of installation and/or during subsequent modifications. UNITEC shall not be responsible and you shall hold UNITEC harmless and indemnify us fully against any and all claims for damages to person (including loss of life) and property arising out of or related to alterations to the equipment not reflected in these documents