7i84u Powering

I'm hooking a 7i84u to a 7i96s and I'm unsure about the power for the 7i84u
From what I understand reading the manual (page 2) there is an onboard switching power supply that will take FIELDB voltage down to logic level if W1 jumper is in the left hand position. So I can supply 24v to FIELDB and it's not going to hurt anything.
Or is that only if I was using 5V FIELD and anything above that I should be using a separate supply for VIN?

Also, from what I understand 
Both field A and field B need to be powered regardless. I've hooked my 24v power (same that is being used on the 7i96s field) to one of the grounds (pin 8) and into pin 1 (VFIELDB) and then a jumper from pin 2 (VFIELDB) into pin 3 (VFIELDA) so they are both powered with 24v.

Right now I've got a 5v line coming over from the same supply that I use for the 7i96s into pin 5 (VIN) and the W1 jumper in the right hand position. That seems to work, I have a flashing green light (CR6 activity) and I can see changes on hm2_7i96s.0.7i84.0.0.imput-00 in HALshow if I power pin0 TB3 (either with 5c or 24v)

Before I let out the magic smoke....
Thanks
M
 

Most normal wiring would be:

FIELDA  +24V
FIELDB  +24V
VIN (unconnected)
W1 LEFT

 

That's what I originally thought (onboard looking after making VIN a safe value from VFIELDB) but the more I looked at it the more nervous I got.
Thanks for the verification

Moving ahead in glacier like strides, limit switches are next.
M