Are these DRO junk help from Electronic Experts

[Tundra Twin Track]

I came across these DRO and proximity switches can they be used for Tachs or anything else useful

[PStechPaul]

The DPM (Digital Panel Meter - not DRO) measures AC current to a maximum of 199.9 mA. The proximity switch outputs pulses when it detects a metallic (or magnetic) object, and may be used with a digital counter or tachometer for RPM. They serve entirely different purposes. Quality is hard to judge, but the datasheets look reasonably good so probably OK.

[Dan_the_Chemist]

There is a basic unfamiliarity with electronics expressed in the original posting. The two devices are a DPM and a proximity switch, and getting from there to a tachometer, etc., is a rather far leap.

If your goal is to make tachometers or anything else useful, then I'd suggest the most direct and useful learning path would be to buy a Arduino learning kit from someplace such as Sparkfun or Adafruit, and it will teach you step by step how to make inputs, outputs, digital outputs, read analog voltages, read counts (tachometer), etc... Your final level of understanding will allow you to make all sorts of useful stuff. The nice thing about Arduinos is that you can use the same basic skill set to make controllers, sensors, etc. Plus - the basic parts are fairly cheap and sort of like Legos...


On the other hand, if you are asking because somebody offered you a bunch of DPM and proximity switches for reallllllly cheap... then no... unless you already know what you are doing they will probably end up in a corner being a reminder of a bad decision.

[Tundra Twin Track]

Thanks Guys it all came from the Dump,never got rained on some one must have chucked just before I got there.There were 13 of those meters ,3 prox switches and 10 KB DC drives in those cast alum inclosers are they called Nema1 maybe.I brought 6 of them home but don't seem to work if had wired correct.

[CCWKen]

Apparently, the previous owner couldn't find a use for the broken parts either.

[wierdscience]

Thanks Guys it all came from the Dump,never got rained on some one must have chucked just before I got there.There were 13 of those meters ,3 prox switches and 10 KB DC drives in those cast alum inclosers are they called Nema1 maybe.I brought 6 of them home but don't seem to work if had wired correct.

Maybe post a picture or two of the KB drives,if they work they could be quite a haul.

[Tundra Twin Track]

Maybe post a picture or two of the KB drives,if they work they could be quite a haul.

Sorry PB not happy

[PStechPaul]

It may be possible to use the proximity switches and the DPMs for a tachometer. Here is a simple circuit:

http://www.circuitstoday.com/tachometer-circuit

You might need to do some minor surgery on the DPMs to change from 100mA to 1mA, and it may be even trickier since they are AC input. Probably not worth the trouble unless you want a learning experience. You can get a proximity sensor paired with a DMM for a tach for about ten dollars.

https://www.banggood.com/4-Digital-LED-Tachometer-RPM-Speed-Meter-Proximity-Switch-Sensor-NPN-p-1045439.html?rmmds=buy

The KB Penta Drives are probably worth fixing. Manuals are available:

http://www.kbelectronics.com/kb_manuals.html

[Mike Amick]

That KB motor controller IS nice. Very configurable. I have one similar on my mill.
I don't know about the rest of the stuff .. but they are gold.

[Tundra Twin Track]

Apparently, the previous owner couldn't find a use for the broken parts either.

Actually the 13 Digital Meters&Prox switches were brand new still sealed up in bubble wrap and instructions