Not getting any output from LEM current transducer (HTR 100SB)

[HVS_2045]

Hi,

1. We have installed HTR 100-SB to measure current on 2 DC drives (FLC 70A). Both the Armature and Field Connections are to be measured. We have currently connected the +/- 15 v supply voltage but we are not getting an output of the transducers.

2. For connection diagram which connection need to follow if you zoom in top view of transducer then from closet to hole (B) - Please refer data sheet HTR 100SB
pin1 is + (+15V)
pin2 is - (-15V)
pin3 is M
pin4 is 0V

However, connection diagram shows.
pin1 is + (+15V)
pin2 is output (M)
pin3 is 0V
pin4 is - (-15V)



Any advice is appreciated.

Thank you

Regards,
HVS

 

[KlausST]

Hi,

In my eyes the datasheet is clear.

1) +U (positive supply)
2) -U (negative supply)
3) M (Measurement output)
4) 0V (GND, reference)

A symbol (connection diagram, schematic) has no reference to mechanical construction. The order of signals does not follow the order of the connector.
And this is godd the way it is. Schematics follow other rules: positive supplies UP, GND and negatuve supplies DOWN, signal (information) flow from left to right. A schematic is to see how the circuit works, what is conected to what, it should be easy to follow the signals.
In best case there additionally are the pin numbers shown next to the signal names.
Example: One physical IC may contain 4 Opamps. On a schematic you may have 4 independent standarized Opamp symbols plus one power supply symbol. All symbols may even be placed on different sheets of the schematic.

Nowadays I often see (mainly for hobbyists projects) schematics using black boxes with numbering in order of the pins of the according IC (package).
I always find it way harder to comprehend the circuit function. This is not how it should be. Hobbyists get it tought the wrong way ... and have hard time to (re) learn to draw schematics the right way when the projects become more complex or more professional.

Klaus