Electrical Questions? Ask an Electrician Online.
Welcome. My name is ***** ***** would be glad to assist.
Can you clarify the posting, please.
"use a transformer isl54 connected to another"
Not sure what this is actually meaning
The ISL-54 is an emergency ballast, which will power the lamp during power outages with a the backup battery pack inside
I will assume you are in need of the ballast for a change out and the other information was just about the ballast being an emergency backup as well and controls one of the lamps during a power outage.
CLICK HERE and you can see the needed ballast, there may be local electrical supply companies who also carry them, but it would be a rare case.
Online is the best source.
Let me know anything further, a quick reply works well