Amp Meter Recommendations

Status
Not open for further replies.
growler said:
I have agreed with your idea of pressure testing from the start.

For some reason they don't want to shut the grill down. I can understand that during the busy times but that just means that someone will have to troubleshoot after hours.

Sounds like they have already changed out the gas regulators and while it's possible to get a new bad part it's not all that probable.
Click to expand...

The regulator the plumber determined was bad was a smaller one specifically for the grill whereas the one that we replaced was a larger one for the ansul system. Two different regulators. The one for the ansul system is electrically controlled whereas the smaller one behind the grill looks like some sort of spring controlled diaphragm non-electrical device.

Grill.jpg
 
Last edited:
Ravenvalor said:
He left us there with the regulators and we waited til after the restaurant closed for the plumbers to show up and replaced them while we were there to disconnect the old and connect the new regulators. After replacing them the problem was not resolved so the plumber opened up a union at the grill and determined there was little to no gas getting to the grill. He immediately assumed that the problem was either a small hose, a smaller regulator or a cutoff valve located on the back of the grill.
Click to expand...

Did they ever figure out what the problems was and if so , what was it?

We are as bad as old women watching soap operas.:happyyes:
 
growler said:
Did they ever figure out what the problems was and if so , what was it?

We are as bad as old women watching soap operas.:happyyes:
Click to expand...

I called this morning and they were waiting for Hobart to come out and have a look see. I will call later tonight when they start to slow down and try to find out what happened. The managers there are clueless though so I am not expecting to learn much.
 
For routine work including measuring current to plug-connected appliances a higher range clamp-on meter can be used with a plug in, receptacle out line splitter with three holes for the clamp meter. 1:1, 10:1 and maybe 100:1 using multiple turns of wire around the hole to make a current transformer feeding the clamp-on. Not useful where you do not want to disconnect the wires, but in some cases you can take multiple turns through the clamp if there is enough slack in the conductor you are measuring.
 
190209-1704 EST

Comments:

Relative to the electrical questions this device shoulfd not be called a regulator. Apparently we are talking about some device that in one box contains both a pneunamtic pressure regulator and an on-off solenoid valve. It is the solenoid valve we are interested in.

It seems the valve is a 120 V AC actuated solenoid valve. As such this will have a DC resistance of some correct nominal value +/- some tolerance. This is easily measured.

There will also be an AC impedance at 60 Hz that changes quite a lot as a function of the position of the solenoid plunger. Least impedance when the plunger is in its returned position (unenergized). A properly functioning solenoid will have a much higher impedance when energized and fully advanced. The currents relative to these positions can be measured. The returned position is hard to measure.


For a known good valve, if you measure the DC resistance, and the AC current when energized at a known voltage, then these values can be used for comparision with a questionable valve. Since there is a great change in AC coil current vs plunger position the AC current can be useful in telling whether or not the valve is fully actuated. Also if not fully actuated the coil will in time burnout. DC solenoids don't havr this characteridstic.

Some more very crude measurements on mu Fluke Y8101 clamp-on probe. Used a 24 V AC 60 Hz source. Voltage not monitored. Just assumed that it did not change a lot. Several resistors. Fluke 27 for current measurement from the Fluke probe. Current calculated from resistance and 24 V.

75 ohm ---
Measured 0.29 mA, times 1000 = 0.29 A
Calculated 24/75 = 0.32 A

350 ohm ---
Measured 0.07 nA, times 1000 = 0.07 A or 70 mA
Calculated 24/350 = 0.069 A or 68 mA

1000 ohm ---
Measured 0.02 mA, times 1000 = 20 mA
Calculated 24/1000 = 0.024 A or 24 mA

2000 ohm ---
Measured 0.01 change, times 1000 = 10 mA
Calculated 24/2000 = 0.012 A or 12 mA
--- used changed because of a residual reading of 0.01

Without more refinment and control of the experiment I can not do much better. This is somewhat an indicator of what can be done.

.
 
Amp Meter UNrecommendation

Amp Meter UNrecommendation

Ravenvalor said:
Will someone kindly recommend an accurate clamp-on amp meter that ranges down into the milliamps? My restaurant customer just spent $2,000.00 to have 2 - perfectly good gas regulators replaced.

Thanks for the help.... :)
Click to expand...

I will just make a point of stating it to help any of the folks who can't put out for the high-dollar stuff.
I just had the Mastech MS2115B I bought in April, die in December.
Meter has great spec's and features (including clamp on DC amps) and USB connection.
The "paper-weight" feature is the only remaining use.
Manufacturer and vendor do not respond to emails and I have yet to find a US warranty/service center.
Just a heads up to help keep other users from ending up in the same situation.
 
Fluke 87

Fluke 87

ptonsparky said:
I use a Fluke 87 in series with the load.

I suspect a clamp for ma would be rather useless for 99.99% of our work.

Typical for Gar, he raises a lot of questions.

My need to know is why you think a clamp on ma meter would have prevented the replacement of pressure regulators.
Click to expand...

I'll second for Fluke 87, the Record function is invaluable for DIAG. I have never had a problem reading even 24V transformer loads and lower.
 
growler said:
Did they ever figure out what the problems was and if so , what was it?

We are as bad as old women watching soap operas.:happyyes:
Click to expand...

I asked one of the managers today and he said that he was instructed by someone to adjust the small regulator on the back of the grill (turn the screw a couple of turns). That seemed to have solved the problem. They would have saved a lot of money if someone would have instructed him to perform this task when the problem first occurred. Such is life..... :)
 
Status
Not open for further replies.
Top