Most controller manufacturers will supply one they will need copies of the prints to build an innerface panel. We always try to add another riser of buttons and run the systems seperatly if we can. Most consultants dont like it but we have found it works well and adds value to the customer vs a temopory interface you throw away (well keep in the back of the shop) at the end of the job.
Thanks for the reply. Most of the mods I've seen, we just rig our own system in the motor room and just double up sometimes, or use a temp button panel at the floors.
When you say add another button riser, are you talking about if a bank of 4 lifts on 1 side you add another in between the lift doors and if the are opposite another on the other side in the middle? Im curious because all lifts I have ever worked on mostly have this any way and another riser is superfluous to needs.