The only thing that I don't like about the Wurtec S3 analyzer, is that if and when you are viewing an input voltage that is close to the lower end of it's detection threshold, it doesn't respond in "real time".
I had an intermittant fault with an escalator. If you lost the motor tach, it would shut down. And of course, if something in the safety circuit opened, it would shut down. Now if the saf circuit opens, you also lose tach, because it's stopped! So I wanted to know which came first, "the chicken or the egg"
So I set it up to observe the tach monitoring relay, and the tach at I think it was 12 vdc, (12 volts is the lowest end of it's detection range). When the unit would shut down, the S3 showed the tach relay dropping out first, and then the tach dropping off after the brake was set. Not a tiny bit, but by quite a bit. Nonsensical. The S3 did not record the chronological state of inputs accurately, if you were near the voltage detection threshold of the input.
Also, I found that since it is a high-impedance input, mere noise would fool it into thinking that it was observing a viable input state, when it wasn't. It needed adjustable drain resistance, to sink noise to ground, and quiet the input.
A few years ago, I called their engineering dept about these issues, and they said they were working on another version. I have no idea if these issues have been addressed or not.
Last edited by Vic; 08/05/12 11:15 PM.