Solid-State Starters - A Wise Investment

What is an elevator starter?

The elevator motor starter is typically located within the controller of hydraulic elevators.  It allows electrical voltage and current to flow from main building power supply to the elevator motor.  When the elevator receives a call to go up, the starter allows power to flow to the motor, which turns the pump, pressurizes the hydraulic system and pushes the elevator up.  There are three general types of motor starters: 

1. Across the line.  This mechanical contactor consists of a set of contacts and coil.  When the contactor coil is energized, the contacts close and line voltage and starting current is connected directly to the motor windings.  In the early days of elevators, this was the only option, and it served its purpose.  Some of the downsides of across the line starters include:

• High inrush currents create stress on the motor’s windings. This stress will cause the windings to move in the end turns of the stator. This will cause the insulation to break down. Eventually, phase to phase shorts will occur and result in early motor failure.

• Across The Line starting puts large amounts of stress on the contactor contacts which, in turn, require a relatively large amount of maintenance.

2. Wye-Delta.  A mechanical starter designed to reduce the incoming voltage at startup.  This is an improvement over the Across this Line starter.  While this was a good option decades ago, there is superior technology available (see #3). 

3. Solid State.   Also known as a soft starter or an electronic starter, it uses SCRs to control the amount of current going to the motor.  The cost of solid-state starters has come down considerably over the years.  They have become standard on new installations and modernization.  

What are the benefits of a solid-state starter? A simple Google search will bring up countless websites highlighting the benefits of solid-state starters.  For good reason!  There are many advantages including: 

• Smooth starting.  Reduces wear on the motor, pump, valve and other mechanical components, extending their life. 

• Phase loss / reversal protection.  Most solid-state starters have built-in phase monitoring.  If it detects, a loss or reversal in phase, it will remove power to the motor, potentially saving you tens of thousands of dollars. 

• Noise reduction.  Mechanical starters produce a very loud bang when starting. 

• Reduced maintenance.  There are no moving parts to maintain.  Eliminating the potential for failure.  If mechanical starter contacts are not properly maintained, they can fail, causing costly repairs. 

• Diagnostics.  Many popular starters, like Siemens, have on-board diagnostics.  This allows easy troubleshooting and less downtime.  

  Can I upgrade my existing mechanical starter to a solid-state starter? 

  Yes!  I do not like to generalize, but in most cases, we would recommend upgrading any mechanical starter.  The technology in a solid-state starter is far superior.  In addition, parts are becoming difficult to source for across the line starters.  

  The cost can vary based on the building voltage and size of the motor.  Most starters can be installed in one or two days.  Permits are required in the City of Seattle / Washington State when upgrading.  Another consideration is whether the starter will fit in the existing cabinet.  A complete survey is usually required.  You can budget $6-10K for most installations.  Or call our Chief Problem Solver, Sean.