Mag Pickup to HSC

I am trying to see if I can hook up a magnetic pickup from a flow turbine directly to a 2080-MOT-HSC without using some sort of preamp?

Any help would be great.

Its a 2 wire mag pickup.

Thank you

We're probably going to need more information on the magnetic pickup to be able to definitively answer that

Why not just go ahead and use a sine to pulse signal conditioner

g.mccormick: any examples of sine to pulse signal conditions?


I have been using a boutique product that takes 0.2-120V sine wave input from generator voltage transformer and output is a square. It works perfectly and reliably but the fellow who makes them is eventually going to retire.

eluder: https://literature.rockwellautomation.com/idc/groups/literature/documents/wd/2080-wd012_-en-p.pdf
"The plug-in module also supports single-ended devices such as limit switches, photo-eyes, and proximity sensors.
On state voltage range: 2.6...30V DC
Off-state voltage, max: 1.0V DC"


doesn't look like it is going to work with mag pickup to me.

We have used a bunch of spectec and have had very good luck with them.

http://www.spectecsensors.com/html_pages/Signal_conditioners_and_preamps.htm

Mag pick ups are typically 5 volt output.

I've used the redlion ASTC inline amplifier on small generators plenty of times. So far trouble free.
https://www.redlion.net/accessory/astc-line-amplifier-magnetic-pickups

BobB > Mag pick ups are typically 5 volt output.


Bob,
I'm pretty sure one can get a mag pickup rated for any of the popular voltages.
We use one we call a 'CGI Prox' - voltage rating is 4 to 24 vdc.

We use them at 24 Vdc, and in one place it connects directly to an Allen
Bradley 1756-HSC module. (High Speed Counter.) The prox reads the
teeth on a gear, the Counter counts the teeth, the PLC does some arithmetic
on the counts and tells us how many pieces were cranked out of the machine.

Been working very well for over a decade now.
Poet.

Mag pickups are typically 2 wire mv peak-to-peak sine wave type outputs. That is why they thpically need to go to a signal conditioner to create a Voltage square wave output for PLC counters.

G,
Where I work most of the magnetic proximity detectors I work around are
three wire. 24 Vdc. We do have a 120 VAC two wire detector - it is in series
with a limit switch making an 'And' circuit which pulls in a 120 Vac relay.

The one I mentioned above is a three wire sensor. Plus, minus, and output
which, as I said, goes straight to a PLC high speed counter. Kind of like this :

(The three wire PNP type sensor. This came from an internet search.)

Poet.

mad poet is talking about proximity sensors which take a power supply (active device) such as https://www.pepperl-fuchs.com/global/en/classid_143.htm


g.mccormick and BobB are talking about magnetic reluctance sensors:
"The MPU is installed next to a drive shaft gear made of a material that reacts to a magnetic field. As each gear tooth passes the MPU, the gear interrupts the MPU's magnetic field, and an alternating voltage is developed"
http://www.woodward.com/EngineSpeedSensorMag.aspx


There must be different types of mag pickups. The woodward site says minimum output is 2V and it goes up to 50VAC. They also specify .5mm (.02") clearance between the mag pickup and the gear tooth, which on a lot of the ****ty turbines I have worked on would not be possible due to wheels that are not round, shaft run out, etc.


I believe the mag pickups that output millivolts are more often used in hazardous environments.
I see mainly proximity sensors on hydro electric turbines tooth wheels since these signals are less than 1 kHz.
mag pickups I have seen on diesel engines and steam turbines where shaft speed is 3600 rpm to start and then there are something like 60 teeth on the gear.


g.mccormick I didn't see any device on the spectec website that takes up to 120VAC as input and outputs square wave.

I have used sensor-solutions for many years in many different applications. They have a great range of products, one of which that may suit your application.
AND NO, I do not work for OR represent them.


https://sensorso.com/

What brand of Turbine Meter are you using? Every Turbine Meter Manufacture that I know of offer some kind of Pre-Amp. Is this for a Oil or Gas application make sure to get the enclosure that is rated for the environment.

The voltage output from the mag pickup is a function of distance the pickup is from gear and the speed of the gear. The spectec signal condtioners can take a max of 140Vpp.

Input Sensitivity: 5, 12, or 30 mVpp
Max Input: 140Vpp (Optional: 200Vpp max)

I use a 4021 on engine flywheels and/or dyno shaft (60tooth) for speed measurement on engine/dyno setup.