Yes, low Voltage has several safety advantages.
Yes you are playing with a spark-gap transmitter or low-tension magneto class creature as can trade shorter time for higher Voltage.
No, no need to tape S1,S2 "together".
Just drop a loose wire-nut over EACH and tape it on rather than munging-up the wire by screwing it on. So nothing can accidentally contact them.
Look at the data plate. What it does is put S(eries) 1 & 2 INTO series with the Armature DIRECTIONALLY. Like a buck/boost transformer works.
So as to "aid" torque.
As load increases, Armature current flow increases, the aiding electromagnetic Field gets stronger automagically to compensate.
But only in ONE direction.
In a 10EE, the motor must be reversible.
One either:
Provides a means of switching between either mode on that data plate when changing motor direction.
Accepts that increasing load will have the drag-down effect actually MULTIPLIED to worsen the situation when running in reverse.
BFD, most 10EE don't usually see heavy loads in reverse unless ... one of we Old Timers are threading AWAY from a shoulder or similar "feature" so as never have had to have to give a s**t how fast we can stop the spindle. To us, "ELSR" is just an annoying nuisance chattered about by the less experienced.
OR... ties them OFF, ignored. When a "4Q" DC drive has more than enough ability to dynamically compensate for load with no such assistance.
And no. It will not "run away". That isn't even a huge risk to begin with on a SHUNT wound motor in general, let alone a Type T. There's the drag of the gearbox, the belts, the bearings, and enough inertia it takes a skosh of time.
The Field strength is the "fulcum" against which the lever of the Armature pries to gain traction. The rungs on a ladder vs a slick pole.
The surface of the pavement, grippy or wet-ice slick under the wheels.
The STEPS on a staircase rather than a wet steel ramp you can trot fast over barefoot and trying to NOT get pregnant ..
.. but not do as well while backpacking a straight-leg infantryman's heavy ammo, chow, and lethal toy loadout for a TAB (Tactical Advance to Battle AKA "ground pounding" and loaded to bring merciless pee).
Weaker the Field, lower the TORQUE!
French racing bicycle, roller blades, or a Nederlander speed-skating a canal of a winter vs a "Big Boy" compounded Mallet-system steam locomotive hauling a hundred-plus car train of coal.
It's the Series-wound AKA "AC/DC" electric motor where the field connection is internal that climbs for low Earth orbit if not sanely Engineered and handled. it has a different concept of "base RPM" altogether from a self-regulating, inherently slef-stabilizing shunt-wound motor.
OTOH, you do not even want to be within range when I'm destructive testing a 3 HP "large-frame" for squirrell-caging!
Just stay TF under 48 VDC until ready to go with a proper DC Drive setup, and fear not.
A SSD 50X used for Field power has an accessable "Fault" signal that can shut-down a mated SSD 514C-XX. Presence of Field first or absnece if lost can be used for "ENABLE" source o ntheArmature supply, not a lot of parts required.
A broken wire at the peckerhead or inside the motor, OTOH?
Shit happens.
BFD. 10EE are not run "lights out". Operator will be THERE.
