[Link: crestron.com]

will they work with 3 way situations ?

Yes, you have to put a keypad on the slave side. This is the same way C4 does it I belive. Basically, the dimmer becomes the ONLY actually load control and the 3-way slave side is just a way to control the dimmer.

This is the way I thought it could be done but talking to tech support lead me to believe that the current dimmers are not three way compatible. If you can confirm that you've installed the current keypads to work in three way configuration, I might go ahead and order some current devices rather than ordering the new EX models that are not shipping yet. I was told you can't mix the two different RF types in the same system

I don't think you are reading or understanding how it works. The dimmer isn't a 3-way dimmer, but you don't need one. Basically the dimmer gets put in the master dimmer location and becomes teh ONLY  load control for the lighting load. The keypad gets put in the slave postition for power and you program it to do whatever you want, including Lights On/Off . 

The reason for a 3-way is to be able to turn the lights on/off from 2 different locations. The dimmer is location 1 and the keypad location 2. When you press Lights ON, on teh keypad, it's really just sending a command to the dimmer telling it to turn on.

Yes you can mix the 2 system, but you have to have a MNET Gateway for the RF models.

That's exactly how I was planning on using the dimmers and keypads but tech support made it sound like it wasn't a good idea. He said the new EX dimmers are going to come with companion dummy switches for the other side. He also made it clear that you can't have EX dimmers mixed with old dimmers in the same system. I think I will call them again to really clear this up.

wait . . these are EX arent they?
the current dimmers dont require a special antenna on prodigy,
they work with the PMC2 as the main antenna.

The current dimmers are EX. The keypads (slaves) to make them multi-location(3/way) are being released this month.

Okay, I think you may be correct with the EX/RF stuff. I know you can use both technologies in a system. the current tstat is RF and can be used with some EX stuff. I'll find out soon as I have 6 RF dimmers and 1 EX dimmer to try and use in my own home.

I don't see why you couldn't use both in a system. I remember they were claiming 100 RF devices, but that was a mix of 70 EX and 30 RF or something close to that.

In light of this information above, how would you handle an install if the home has rooms with 3 way wiring set ups currently in place?

One side: Dimmer

Other side: EX Switch or one of the new multi use keypads?

I would call tech support again to clear this up. I had the same problem with one tech saying yes you can and another tech on a repeat call said no you can't.

I had this same issue working with the Cameo Express CLW-DIMEX-E and there is no slave switch for the Express line; however I was able to use the CLW-DIMEX-P & the CLW-SLV-P (Slave), on the same project the only physical difference is the E has green LED's and the P has white LED's in my opinion the white LED's on the P line looked better because the LED's were brighter. I was also using a CP2E processor and you can't use the CLW-P's with prodigy.

NOT the switch, just a keypad. the wiring would have to be changed slightly. Basically you are making it a standard one sided dimmer - no 3-way. You are using the existing 3-way feed to power the KEYPAD which can then be programmed to on/off/raise/lower the lights.

However, i saw a relased for a slave dimmer option in an email blast.

Thanks Sofa. Could the switch be used on the other end from the dimmer if that is what was preferred though?

Another thought: Is there any reason why you could not put a Lutron Claro 3 Way Switch on the other end from the Crestron Dimmer?

It is not a 3/way switch. The end without the load is just a point of control. All it needs is 120 volts to power up the device. The communication is RF to make it work like a 3/way switch.

I understand that is keypad is not a switch....simply a point of control. But if I wanted a "switch" in the location opposite the EX Dimmer (can't remember the model 3), how would I accomplish this. The goal is to be able to switch the light on and off even if the Crestron system was not operational for some reason.