I seem to remember having read that 3 is the recommended max. -Or was it that they approximatly use 3VA each?
In any event, when you use contact-tracks like the 5146, there can be some burning on the contack-pads. (which must then be cleaned, and they are good again...)

I switch 3 coils with my 5146-type tracks for a long time, and everything is working fine for years.
I use a separate 100VA transformer (of the TITAN brand) for this control, and I havent bothered with the inrush current. (-which is certainly there, but the old trafos can handle it easily)

Ha! I get what Mikey is saying; The 5146 tracks are notoriously flimsy and unrealiable!
I atually dont use any of the M-track contact-tracks, but rather the K-track equivalent. (That´s why I said "like 5146").
Once installed and working, they are quite dependable, just DONT touch them with with your fingers or anything else that is not a sprung slider!!!

I was atually decided on to NOT use these tracks, but with time I found that they took well to repairs and being left alone.
I now fully rely on them for branchline control (3 pieces), and 2 other pieces on my main-line, whose job it is to count sliders in order to distinguish between freight and passenger trains. (these 2 last pieces go to a PLC digital input, and draws practically no power)

Hi Jim,

I've set up my analog layout using the 7072 control boxes. For a few turnouts, I've got the turnout, two home signals and two advance signals all controlled by a single pair of 7072 red/green buttons with blocks ahead of them to control passage. I cleaned and tested each turnout and signal to be sure their solenoids slide easily, and their mechanical linkages, etc were working reliably, so they change predictably with a single push of the button. So far, so good. I'm keeping an eye on my grandkids when they operate them so I don't fry anything, and I've got quite a few 6001 trafos to not overload the L circuits on my 6627's while running.

I also was careful to only use 7072's which aren't fried/warped as they tend to be in the Used market.

Someday, I'll take the plunge on using circuit tracks; my wiring under the layout is enough of a (labeled) rats' nest as it is...

I hope this helps, from one M-track analog guy to another!

Brian

Hi Jim
There is a maximum number of solenoids you can connect to a slider-operated contact track. Märklin used to say TWO and I think three is a reasonable limit. Driving a large number of solenoids simultaneously usually slows down the train because the magnetic power delivered by the trafo is 30VA and dpread on the B (Bahn) and the L (Licht) outputs.
BUT the huge drawback is that these solenoids are tied forever (E.g.: signal 1 red with signal 2 green) which is annoying and problematic.

There is a simple solution to this
- install a diode (1A or more) in series with the yellow (16VAC) of the Märklin transformer anode facing the trafo.
- install another diode on each contact track (cathode towards the track)

In this way, solenoids become independent again without using a zillion contact tracks to make intelligent automatisms
The control boxes may be connected the usual way without any issue the O (ground) is sent to any solenoid when you press the button.
Little drawback: the power to drive each solenoid is reduced (half wave instead of full wave) so the switches and signals must be in good condition. On the other hand it reduces the risks of burning a solenoid.

A typical Märklin transformer delivers 16 VAC 1 A on the yellow accessory plug so using very common diodes like the 1N4004 (400V max reverse voltage) up to 1N4007 (1000 V reverse voltage) 1.50€ for 100 pieces on Aliexpress

Cheers
Jean

(former engineer in Electrotechnics and electronics who has forgotten loads of things: cannot do integral or derivative calculus anymore )