Need help for lem 25 np current sensor

[amruta kulkarni]

current sensor

am using lem 25 np current sensor i need help in using this sensor
the data sheet with this sensor is not clear
what are the pins 123 in and 456 out used for ? what supply should be given to these pins
pls guide me in using this sensor

 

[sinoo_jahagirdar]

current sensor

Got the output?.........................................................................................

 

[karesz]

Hey "des.- eng",
since time has a component serial number!?
Why dont you search for Lem`s data sheet self; if you wish really help some thing pls?
K.

Added after 5 minutes:

Hi amruta kulkarni,
I think the Lem 25 NP is not the full type, can you tell us pls what for exacter version you has to use, or maybe better is to attach your data sheet(hes address)...
They are the versions of 25NP sensors:
https://www.lem.com/index.php?site=...ch=25np&limitstart=0&outputtype=instantaneous
K.
P.S.:
If you has LA25NP, you can see it from the attached data sheet;
the connection of pin Nrs1-10 is specially depend of the desired current range...

 

[amruta kulkarni]

thank for relpy
the sensor code lem LTS 25 NP
i am using it to measure current drawn by the bldc motor
with connection tat i have made
the sensor shows variation from 2.48v to 3.28v for the current from 0.05 amps to 7.25 amps
i want its varition from 0 to few votls

Added after 57 minutes:

**broken link removed**
this the data sheet

 

[sinoo_jahagirdar]

U can go through this file ...Hope u get the right o/p...

 

[amruta kulkarni]

i have this data sheet but i am not understanding what r those 123 and 456 input and output pin what to connect to these pins
plz help

 

[karesz]

Hi Amruta,
As I wrote; they are to arrange in depending of your current sensing range.
If your desired sensing range = +/-25A:
connect 1,2&3 parallel for, say input curent lines an the 4,5,&6 to for the output of current(or sensed) lines.
But if you wish to sense in full range of +/-12A:
Pins 1,2 and 5,6 parallel connectedand added to that pin3 (the 3th coil is in serie connected with the both, befor parallel connected other sensings coils) and pin 4 is as the (i.e.) output for sensing line , end pin 1,2 are then the input lines for your current sensing.
With same logic can you only +/- 6A sens with the same sensor if you do the sensings coils arrange as follows:
Sensed current line input= pin Nr.1, output = Pin Nr.4 and the 3 sensing coils are serial connected(=close pls. pin2 to 6 & 3 to 5).
Remeber pls, these input/output are only the current-line (or sensors) I/O!
The 3 other pins(+5V,GND (0V) & Out are isolated of their group, their are the secondary part/side of these sensor... If you has a minimum 2 KOhm load on that output(to 0V), you will measure at nominal input current of 25/12 or 6A a value of 2.5V.
Greetings!
K.

Added after 8 minutes:

I saw yet, sorry, that you are wishing the output signal between 0 and some top value for 0--7A, in that case you must select some another, called unipolar, sensor (I dont no if their are to find from LEM) other take an OpAmp as vlevel shifter _add a ca. 2.5V into a buffer amplifier with your signal...

 

[amruta kulkarni]

hi i need help to test if earthing at my place is correct or no plz guide to check earthing using digital multimeter..........

 

[karesz]

Hi,
these is a special subject alone_I think; it will be better to open a new one topic for that...
k.

 

[ahliang530]

Hi Amruta,
As I wrote; they are to arrange in depending of your current sensing range.
If your desired sensing range = +/-25A:
connect 1,2&3 parallel for, say input curent lines an the 4,5,&6 to for the output of current(or sensed) lines.
But if you wish to sense in full range of +/-12A:
Pins 1,2 and 5,6 parallel connectedand added to that pin3 (the 3th coil is in serie connected with the both, befor parallel connected other sensings coils) and pin 4 is as the (i.e.) output for sensing line , end pin 1,2 are then the input lines for your current sensing.
With same logic can you only +/- 6A sens with the same sensor if you do the sensings coils arrange as follows:
Sensed current line input= pin Nr.1, output = Pin Nr.4 and the 3 sensing coils are serial connected(=close pls. pin2 to 6 & 3 to 5).
Remeber pls, these input/output are only the current-line (or sensors) I/O!
The 3 other pins(+5V,GND (0V) & Out are isolated of their group, their are the secondary part/side of these sensor... If you has a minimum 2 KOhm load on that output(to 0V), you will measure at nominal input current of 25/12 or 6A a value of 2.5V.
Greetings!
K.

Added after 8 minutes:

I saw yet, sorry, that you are wishing the output signal between 0 and some top value for 0--7A, in that case you must select some another, called unipolar, sensor (I dont no if their are to find from LEM) other take an OpAmp as vlevel shifter _add a ca. 2.5V into a buffer amplifier with your signal...

hi there, i have the same problem of using this transducer too..
i am confuse that how to use this transducer is that current must go trough (connect to) the transducer coz what i refer to data sheet it look like need to connect the current into the component input and output for the 6 pin ? or i check other web page that said transducer that is only pass through the wire to the hole provided and it will detect and convert it to output voltage.

 

[karesz]

Hi,
Read in detail my post from "11 May 2010 10:48" pls!
Its clear, your 1...6 pins are the "Current side" pins
OK the vendor has not so very good described with Input & Output, but their means:
"Input"= current will flow into the sensor & at these pins
"output"= current will flow from sensing device, back into the main system, to the Load...
The out pin Nr7 HAS NOTHING TO DO WITH THE CURRENT OUTPUT!
They (both "out`s") are isolated too...
These Output is the sensed input current; transformed to voltage, & is referenced to pin Nr8, here called "0V", what is the reference too for the "+5V" supply(pin Nr9).
K.

 

[ahliang530]

Hi,
Read in detail my post from "11 May 2010 10:48" pls!
Its clear, your 1...6 pins are the "Current side" pins
OK the vendor has not so very good described with Input & Output, but their means:
"Input"= current will flow into the sensor & at these pins
"output"= current will flow from sensing device, back into the main system, to the Load...
The out pin Nr7 HAS NOTHING TO DO WITH THE CURRENT OUTPUT!
They (both "out`s") are isolated too...
These Output is the sensed input current; transformed to voltage, & is referenced to pin Nr8, here called "0V", what is the reference too for the "+5V" supply(pin Nr9).
K.

thx for your explanation , but is that work with if i just pass through the wire to the hole(middle of the component) in the transducer? because i see some of the ppl measure the current with that kind of method ? is that the component can measure the current in 2 different way?

 

[karesz]

Hi,
I can imagine as working element too, but I dont no_I would make never so a version!
I know only:
It is a system with 3 current sensing coils(maybe have all windings only 1 turn, but we dont know), and your sensitivity is "programmed" or setted if you will connect their all 3 windings in parallal or partial in serie or all serial...
If you will pull only a wire through the hole: its in my opinion a half or less (maybe a third) winding/turn only, with corresponding smaller sensitivity, and what more worse or bad is: through the diverse positioning/moving of your wire to the ferrite core (inside your sensor) it will have a very unrepetedly/unreproducible sensitivity!
I would tell: forget it, then your wire position must be absolute stabil (not inpossible, but you must arrange /design it)!
K.