The Siren Board

Can any of the following sirens be equipped with battery backup:

• Federal
  2/2T
  3/3T
  5/5T/7/7T
  2T22/3T22
  STL-10
  STH-10
  SD-10
  500
  EOWS Series
  Thunderbeam RSH-10
  
  ACA
  Banshee
  P-10
  P-15
  P-20
  Allertor
  RM-130
  Allertronic Series

EOWS probably do.

As I recall, the RM-130 had battery back-up as at least an option. I believe the Alertronic had batteries as well.

The STL and the STH could be equipped with a high-torque DC motor. Similar to that of how a 2001 is configured. It would take some modifying, but I can't see why it wouldn't work.

Even though it's not listed here's my idea on a 'bolt. DC motor for the blower and rotator, inverter and transformer for the chopper.
The EOWS series sirens are battery powered. Ditto with the Alertronics I think. Hm.. I think the rest you listed could probably be retrofitted with DC motors to drive them on battery power.

I've never heard of a 3T before.
Any siren could with the right kind of battery and equipment.

Out of that list, only the EOWS, Alertronic and PN-20/RM-130. When it comes to electronic sirens, really all of them are battery powered.

Yes, every Whelen model that I know of, from the WS-1000 on, has batteries. They've had their 30 minute minimum run time as a selling point from day one.

The 2/2T uses a series-wound motor and could be run from DC.

This sn't on the list, but a. P-50 can be put on battery backup. The P-50 I tested one week ago had federal battery boxes on it.