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Note: this question updated, please see the major edit.

I need to wire four or two of accelerometer and perform data-acquisition with a single-ended daq device. It seems this is single ended output, and I want to use the DC output with a CAT6 cable for each accelerometer. The model I deal is LNC, so it has both power ground and signal ground. The manual/data-sheet shows the pin numbers of the sensor as: A, B, C, D, E, F as:

enter image description here

Since I don't have split supply, I will make a +/-12V split supply from from two identical 12VDC SMPS power supplies.

Below I draw how I'm planning to wire the setup for two accelerometers:

enter image description here

My question is:

Since I will have one split supply and two or more accelerometers, is it fine to use the same excitation for all of them as shown above in my diagram? Is there anything wrong in this way of wiring?

MAJOR EDIT:

I blew up one of the power supply when playing with "DC OK".

So here is my new setup:

enter image description here

I will use a regulated 24VDC power supply and a rail-splitter circuit with a virtual ground instead.

But I'm still afraid if I might cause damage because of wrong grounding. I checked B and F are internally connected in the accelerometers. So power ground and signal ground are connected to each other. In the DAQ side VGND might be earthed(single-ended earth grounded config.). But I will not use earth wire for the 24VDC power supply. Am I safe from shorts in this case? Can I trust the isolation resistance even though Im not gonna use the earth wire on the left side(24VDC power supply side).

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    \$\begingroup\$ I will make a +/-12V split supply from from two identical 12VDC SMPS power supplies. That will only work if those supplies do not have a mains earth or the low voltage - (minus) output is not directly connected to the mains earth. If this is not so you would short circuit one of the supplies. \$\endgroup\$ – Bimpelrekkie Oct 2 '17 at 14:57
  • \$\begingroup\$ You should aim for a star ground (see: analog.com/en/analog-dialogue/articles/… ) way of connecting the grounds. It is common to make the star grounding point at the most sensitive point and that is the ground input of your ADC. \$\endgroup\$ – Bimpelrekkie Oct 2 '17 at 15:00
  • \$\begingroup\$ @Bimpelrekkie Can I verify it by ohmmeter between -VDC and the earth? Or can it be seen from the data sheet? This is the power supplies I have: docs-europe.electrocomponents.com/webdocs/14dd/… \$\endgroup\$ – user1999 Oct 2 '17 at 16:08
  • \$\begingroup\$ Yes use an ohm meter to be sure. Any experienced EE would/should do the same because then you know for sure. According to the dataheet there should be no connection so they should be safe for +/- 12 V like you intended. But still, measure it just to confirm. \$\endgroup\$ – Bimpelrekkie Oct 2 '17 at 18:53

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