Personnel Lifts

Powering a lift with a three phase converter requires special consideration. In the first instance there are several questions that need to be asked of the lift manufacturer:

What is the total power consumption at the maximum load point, including all power consuming elements but excluding additional power for motor starting ?
Please list loads that are connected phase to neutral, stating which phase is used in each case.
What is the maximum power for standby battery charging ?
What % imbalance in the three phase-to-phase voltages is acceptable ?
When regenerating power back to the 3-phase supply, what is the maximum acceptable supply imbalance, voltage / current / impedance ?
When starting the phase converter from lift demand (the button), are there separate relays / contactors for single phase input and 3-phase output and is there a time delay between them ?
When the 3-phase converter detects low voltage (phase L2 to L3) and supplies momentary 'boost' for starting, what is the tolerance on momentary low and high voltages ?

The phase converter is not designed for continuous unattended operation. If it is to be used continuously the warranty is void unless it is installed in such a way that it is started and stopped ‘on-demand’ by the load with a duty cycle of less than 50%.

When used in a critical application we recommend that they are installed in a 2 x 100% duty/standby configuration so that the site is unlikely to be left with a total system failure.

It is also important to check that all single phase loads that are part of the unit can be taken from L3 to neutral or can be powered from a separate single phase supply, otherwise a delta-star transformer will be required as well as the phase converter.

Once you have established all of this information please contact our technical team on 07572 532884 to discuss your options as a custom solution may be required.