Electronic Alarms and Home Security Devices - DSC PC1555: Keypads won't turn on

I have a DSC PC1555 panel with 2 wired keypads. Today I was trying to add a wireless receiver module (RF5132-433). I followed all instructions from the module, but I forgot to unplug the battery during the installation. After I wired the module the keypads don't show anything (they seem completely off). I removed the wireless receiver module and hooked up all the cables (including AC power) just like they were at the beginning. The keypads are still off. Is it possible that I shorted the board? How can I diagnose what's wrong when my keypads are off?

I think I figured out what's wrong. I accidentally shorted the two transformer cables before connecting them to the board. It looks like the transformer is dead (it doesn't output anything). Is there a way to reset the DSC PTD1640U transformer, or do I have to buy a new one?

If this transformer has a PTC device, unplug it for a while and let it cool off, and it may reset. Many have a 1 shot fuse built in, and once they are shorted, there is no field repair for them, and you will need another transformer.

It looks like this transformer is discontinued. One site suggests replacing it with the ELK TRG-1640 transformer. It has mostly the same specs except the original transformer is a 40VA transformer and the ELK is a 45VA transformer. Is it ok to substitute it?

Yup, good to go with that transformer.