Can I power my WTIU off of a Z4000 instead of using the WTIU power supply?

I would generally tell you no, this is not ideal.

The WTIU takes time to boot up and be ready for operation. It is an electronic component and needs it's own power source. Yes, like the OLD TIU, they did build in a regulator circuit and in theory can borrow power from fixed 1 input only.

DO NOT FALL INTO THIS TRAP.

They purposely ship the WTIU with a dedicated power supply to plug into the aux power in port of the WTIU to keep it powered and booted up- since again, it takes time for the operating system to start (much longer than the previous TIU). Use what they gave you- the external power supply and plug it in.

@CyrilW posted:

I thought I read somewhere that I could either use the phone port or the 14v port to power a WTIU. Is that correct?

Thanks.

I'll also add, you got some of that terribly wrong.

The "phone port" on the Z4000 and the black box you are showing is the Z4000 remote receiver box. NEVER plug anything other than that known compatible Z4000 receiver into that port. Anything else will likely damage the Z4000 and whatever you plugged in. https://mthtrains.com/40-4001

That box will not work with the new WTIU- because the new WTIU no longer supports the DCS handheld remote. In other words, the 900MHz items are pretty much now no longer supported. In the past, when you had a TIU and DCS remote both using 900MHz communications, the radio receiver for the Z4000 could be used to make the Z4000 variable channels be operated from the remote as Z4K channels. I suppose maybe one could still use a DCS remote and the Z4000 receiver with a Z4000, but it seems a bit of overkill with the DCS remote and it won't talk to the WTIU over wireless.

Further- on the using 24V accessory power of the Z4000 to then power the WTIU logic power via the aux in port with a cable- I further do not recommend this.

I haven't tested the new WTIU aux power in port, but I do remember that on the TIU, I think there was a polarity or common reversal between the aux port and the fixed 1 input.

In other words, at least of the TIU, the ring of the coaxial aux input jack becomes a short to the red input post of the fixed1 input if the transformer is sharing common (which a Z4000 is common U between channels).

So again, another nail in the coffin of sharing power and using 14V from a Z4000 to "power" a WTIU, I don't think the risk of getting it wrong and possibly causing damage to the quite expensive WTIU makes any sense- especially since they sold it with a dedicated power supply.

Update:

#1 the WTIU aux power input jack is labeled 16V-22V AC/DC, so minimum recommended power voltage is 16V- not the 14V output of the Z4000

#2 The power supply included with the WTIU is 16V DC 1500mA

#3 I checked with a meter for continuity on the WTIU, between the aux power input jack and the fixed1 input channel and did not see any continuity. It appears that portion of the power circuit is different compared to the TIU, but I still advise caution in a shared common power source- between aux input and the channel inputs. I don't know the isolation or voltage constraints and would say the best bet is to use the included wall pack that comes with the WTIU or another dedicated and isolated transformer or power source that meets the specifications 16-22V AC or DC, minimum capacity of 1500mA- possibly more if using a bunch of AIUs- something has to power those relays,.....

#4 Testing a revision L TIU- the power subsystem was as i remembered it- tricky. The aux power in port polarity is related to fixed1 input, but from a "standards" (using that term loosely) the ring tip of the aux power shows continuity to the red input post of fixed1 and the center pin of the aux input jack shows continuity to the black post. This is why I said it could be a real problem if you wire something like a Z4000 or even a Z1000 brick and use the aux 14V output of either of those- common with the track power channel- that polarity at the input of the TIU aux power jack could lead to a short in the TIU, and that could be a really bad day.

While I did not find the same possible electrical connection pairing and possible short circuit as with the original TIU, it's not like we have reverse engineered or tested the circuit and everything has a max voltage. Even if there is no continuity- that could easily be across electronics with maximum voltages- and so knowing that, and the cost of the WTIU, I'm not going to test shared common power source between track channels and aux power in of the WTIU.

The WTIU came with a power supply- use it.

Thank you for all that great info @Vernon Barry. Much appreciated. I'll stick with the included power supply and maybe get a power strip so I don't have to keep removing and inserting the barrel plug to turn it off and on.

@CyrilW posted:

Thank you for all that great info @Vernon Barry. Much appreciated. I'll stick with the included power supply and maybe get a power strip so I don't have to keep removing and inserting the barrel plug to turn it off and on.

My casual advice- why are you turning it off and on each running session?

If anything the DCS explorer and the WIU taught me is the highest chance of corrupting those previous devices came when booting them up and down frequently could lead to a bricked device if the boot power on sequence is interrupted. The new WTIU combines the networking components and logic of the WIU into the TIU and takes time to boot up before being ready to use and receive and send commands like the necessary watchdog out of a channel.

Do you power down your home wireless router?

I could list dozens of reasons, but again, the WTIU comes with a dedicated power supply. It takes a decent amount of time to boot up. It connects possibly to your home network, or if using in MTH mode to stand up it's own wireless, it has to stand up that network and your phone or tablet has to connect to that.

So yes- 100%, I'm advocating- leave the WTIU "ON"24/7, especially when attached to your home wireless network.