Magnetic susceptibility loop

[electronicsensation]

Hi,

I am working on a magnetic susceptibility sensor to interface it to our existing electronics board.

The original system consists of a loop (through which we pass specimen) and a meter which powers the loop and receives pulses of certain frequency (depends upon specimen). This meter powers the loop and receives pulses just by using 2 wires i.e. there are no signal wires in addition to power cable. When the loop is not connected, voltage is about 10.1V dc but when loop is connected, i can observe sharp drops to zero volts every 1.76ms (when there is no specimen through the loop).

My questions are:
1. Is this a Phantom powered loop?
2. when I hotplug the system to power supply, it blows power supply fuse due to the fact that loop sends very high frequency pulses and effectively shorts power supply terminals but settles down after a short duration. any ideas to resolve this issue?

https://obrazki.elektroda.pl/6013979900_1389023773.jpg

Thanks!

 

[crutschow]

Without more info on the sensor it's difficult to make an informed guess as to what's happening.

 

[electronicsensation]

Following are the links for detailed information on the whole system:

**broken link removed**
and
**broken link removed**

apart from that, what other information are you looking for?

 

[crutschow]

I'm have a problem understanding your questions.

1. I don't know what you mean by "Phantom powered loop".

2. Hotplug what system to what power supply?

What is the existing electronics board you are trying to interface to?

If you could show a diagram with all your components and connections it would help.

 

[electronicsensation]

Please refer to following diagram:
https://obrazki.elektroda.pl/2843874200_1389174420.jpg

Magnetic susceptibility system consists of: 1. MS3 meter and 2. Magnetic Susceptibility Loop.

Loop is connected to the meter through a coaxial cable "ONLY". So the same coaxial cable is used to excite the loop and data transfer.

Meter is connected to the PC over USB interface and powered through a data logging system.

Data logging system connects to all other sensors and motors and connects to the PC over Ethernet and also contains various power supplies. There is an electronics board inside it which contains all signal conditioning circuits and FPGA.

Now back to your questions:

1. I don't know what you mean by "Phantom powered loop".

When we use same pair of cable for power and signal communication we call it Phantom Power, correct?
check this for reference: https://en.wikipedia.org/wiki/Phantom_power

2. Hotplug what system to what power supply?

I mean hotplugging MS3 meter to +5V power supply in data logging system.

Now my problems are:

1. I want to understand the interface between MS3 meter and the loop. What do we call it and how it works?

2. When I hotplug MS3 meter to data logger, loop sends out pulses of very high frequency and effectively shorts the power supply although it stabilizes very quickly. This response affect the fuse and it blows. I want to prevent the fuse as it is just annoying to keep replacing.

 

[crutschow]

1. Exactly how the meter works may be proprietary. The manufacturer has that info and however much they want to tell you is how much you will learn.

2. Why do you need to hotplug the MS3 meter to the data logger? Doesn't the MSE meter have an on/off switch? If you must hotplug then perhaps you can use a slow-blow fuse to minimize blowing from the surge.