There aren't any 'specs' that I know of, on how many motors can be wired, but Peco says "one unit is enough to power the average layout"... whatever that means.
I do know that simultaneous operation vs recharge delay has been an issue.
Seems to be a little agreement around six motors.
They probably should be all the same type of switch motor or they will draw different
currents in parallel.
If the snap of the points seems a bit weak, add another parallel cap; recharge will be slower.
Prolly not enough duty cycle to affect other components.
But I have not tried it.
A Capacitance Discharge Unit can be the power source
for an unlimited number of turnouts. In most cases, the
push of a button 'throws' only one set of points. The
other turnouts stay idle, thus draw no current.
However, on my layout I had two diode matrix controlled
yards. Push one button in the 'target' yard track and all
points in the 'route' are set. To provide sufficient current
for the sometimes 4 or 5 turnouts in such a 'throw' I used a common
household DOORBELL TRANSFORMER. It provided
18 volts AC, unknown current, which was the source
for my home built CDU which had a built in rectifier and 'rapid'
recharge circuit. I had no 'slow' snaps...all my Pecos
immediately moved properly.
Maybe not so common, at least on this side of the Atlantic.
The British firm Peco calls their turnouts "points", since that's what the British Railway types call what we yanks refer to as a "switch" on our full-sized railroads, and a "turnout" on our model railroads. Peco also calls their twin-coil switch machine a "point motor."
However, the term "switch machine" includes both solenoid, (like Atlas's "twin-coil switch machine") and actual (DC gear) motors, (like Tortoise, Switchmaster etc.) as well as servos, (like those from Walthers and Tam Valley)
Arguably, even mechanical linkages could fit into the "switch machine" general category. (like my purely mechanical, cheaper, "Tortoise" substitute, "$5 Switch Machine")
I think the term "switch machine" rather than "switch motor" is a more accurate, and also more common, way of describing any device that moves the points of a turnout, rather than "switch motor" which tends to be more closely associated with DC motors, rather than AC or DC solenoids, servos, or mechanical linkages.
The responder who pointed out that a CDU could damage a "switch motor" (meaning the DC gear motor type) is quite correct. Even though the general context of the thread leans more toward solenoids, he couldn't know, for certain, which type of "switch motor" the OP had. No one wants to see an expensive Tortoise motor go up in smoke.