Does ZW-L eliminate the need for a TPC?

Yes.

The only thing to be aware of is that you will need to use the CAB-2 to dial up the voltage on your command loop as well.  There isn't a way to program the handles so that one will always be at 18 volts and the other will be variable.  They either are all controlled by the remote, or none are.

(this assumes your power requirements are within the single channel (handle) capability of the ZW-L, 180W.  If you are using a TPC that can deliver more power to the track and paralleling 180 bricks on the input, then this is not the answer for you.)

The need to dial up the voltage for command loops  is not a big deal in my mind, but some people used to complain about the ZW-C because it had different behavior when in command mode for the inner and outer handles.  (inners would start at the max voltage immediately when in command, the outers would be dialed up to get what you wanted). 

Personally, I like they way the old ZW-C outer handles (and now the ZW-L for all handles) work, but some had the opposite opinion, preferring the old ZW-C inner handle behavior of starting at max.

The thing to keep in mind is that the command/conventional switch on the transformer defines the transformer's mode, it has nothing to do with the motive power.  Any TMCC/Legacy engine will behave in command mode assuming it can see the base, no matter what the transformer switch is set to.

-Dave

Dave,

Thanks. I like the direct short answer first!

Just to be sure I understand...ZW-L in command mode:  Block 1: I address A with the CAB-2 and dial up to 18v. and use it to run the command engines:  I address D and dial up and down the voltage for the conventional locos.  I can also address B and C and use them however I want to so long as the entire voltage and amps do not exceed the limits of the ZW-L.  I'll be rewiring my layout and retiring the TPC for now.

Again thanks for the quick and very helpful response.

ed

ToledoEd posted:

Dave,

Thanks. I like the direct short answer first!

Just to be sure I understand...ZW-L in command mode:  Block 1: I address A with the CAB-2 and dial up to 18v. and use it to run the command engines:  I address D and dial up and down the voltage for the conventional locos.  I can also address B and C and use them however I want to so long as the entire voltage and amps do not exceed the limits of the ZW-L.  I'll be rewiring my layout and retiring the TPC for now.

Again thanks for the quick and very helpful response.

ed

100% correct with the minor clarification that the ZW-L is limited to 180 W max on any  handle (the last of which will limit at 80 W if all the others are maxed out due to the total available being 620 watts).  That's a highly unlikely scenario unless you run 3 trains all right near the 180 W limit. 

To be more precise, the last handle will max out at the lesser of either 180 W or 620 W minus whatever the other 3 handles are consuming)

Sorry if I made my response more confusing than it needed to be.  I only mentioned the 180W limit because some of the larger TPCs can deliver more than that to the track.  It sounds like you are probably not doing anything that is that power hungry or complex, so you should be fine.

Glad it helped!

-Dave

Dave, the only one confused was me. Your response was clear and very helpful. I've already pulled my TPC.  

I understand that the ZW-L has essentially four TPCs inside.   To use with a Legacy or TMCC remote, you still need the command base, correct?   It doesn't have a command base built in as well?

Second question, anyone try using the ZW-L to control other scales at 12 volts?   I imagine setting one of the dials to 12volts max, rectifying the AC track power to DC, which then connects to for example, HO track.   Thus allowing remote control of the HO track voltage through the ZW-L(using the TPC) and the handheld to run a HO locomotive?   Any problem in doing this?

The ZW-L would be set to command? allowing the remote to control the voltage from each of the embedded TPC circuits?   Each of the four output circuits would be max limited voltage based on the handles and dials, and varied by the remote between zero and that dialed-in max voltage?

Thanks for the help, I am just getting into Legacy/TMCC and thinking about possibilities.