Replacement Transformer - Output = 24 volt AC at 1660mA ,
without Power Cord - Plugs directly into electrical outlet ( your possibly an extension cord would be used ).
Model # F5-AC2440VA-2S, 24 volts - 40 volt amps rating.
Replaces Rainsoft PN = OTE-40-24-ACDC-N PTC, also referenced as PN 17000.CABLE used to connect from the Transformer to the Valve Control is sold separately ( Cable - Rainsoft 2 wires 18 AWG and Connector = PN RS92616A )
NOTE: There is not "+" or "-" ( polarity ) on this or any other AC ( alternating current ) transformer.
Polarity only applies to DC ( direct current transformers ).
Also NOTE: Older models had a 3rd wire ( Center - Ground )- that space
is left empty ( referenced in our alternate photo ).
This is no longer used,
and was never "necessary".
None of the 24 AC transformers sold for water softeners has a "Ground" on them.