[40 VAC to energize 24 VAC relay coil?]

Okay, Thanks.

[40 VAC to energize 24 VAC relay coil?]

Thanks for the help on that.  The online calculator I used came up with .73 watts also but said a 1.22 watt is a safe bet.
I'll give it a try.

[40 VAC to energize 24 VAC relay coil?]

Okay, the manufacturers literature states that the 24 vac relay consumes 1.1 VA so that would equal 45.83 mA using ohms law.

Using this online LED resistor calculator... http://ledz.com/?p=zz.led.resistor.calculator i came up with this...

Supply voltage = 40
Voltage drop across LED =24
Desired LED current = 45.83 Ma

Resistor should be:
390 Ohms
1.222 Watt

Did I do that correct?

[40 VAC to energize 24 VAC relay coil?]

When I have 40 VAC present I need a contact closure for a control circuit.  Does anyone know the best way to drop the 40 VAC down to 24 VAC to energize a coil on a cube relay?  I was thinking of putting a resistor in series but do not know how to calculate.  any other ideas?