Products > Test Equipment
Best handheld dmm, at any price?
VEGETA:
--- Quote from: Synthtech on April 12, 2018, 09:07:09 am ---Measuring capacitance with a multimeter is like measuring DC with an oscilloscope.
--- End quote ---
I do it.
Scope is suitable for this but if I want just a number and not a signal, I would use DMM.
Synthtech:
--- Quote from: VEGETA on April 12, 2018, 09:35:53 am ---
--- Quote from: Synthtech on April 12, 2018, 09:07:09 am ---Measuring capacitance with a multimeter is like measuring DC with an oscilloscope.
--- End quote ---
I do it.
Scope is suitable for this but if I want just a number and not a signal, I would use DMM.
--- End quote ---
Agreed. I use my multimeters generally for checking capacitance values of new parts and reach for the LCR meter when I want to check ESR or other parameters or for tight tolerance selection.
LoFi:
--- Quote from: VEGETA on April 11, 2018, 10:26:09 pm ---
--- Quote from: 001 on April 11, 2018, 09:41:34 pm ---
--- Quote from: VEGETA on April 11, 2018, 10:21:25 am ---And I have a question: Why Fluke 87 is always the most used one? always considered the standard... can someone explain this?
--- End quote ---
The same story like Kalashnikov rifle.
--- End quote ---
Hhhh not really. the AK47 has real advantages over the others, known and measurable advantages.
--- End quote ---
Fluke pioneered the development of DMMs back in the 1970s and built their reputation on good performance, reliability, accuracy, robustness. No one else has quite that kind of long-running track record, and that counts for a lot with people who bet their lives and livelihoods on how well a multimeter performs.
Re 'real advantages'; many cheap meters are pretty accurate these days. What might a Fluke 87V do that these cheaper meters don't?:
- extremely fast continuity check. It's strange that most other meters don't seem to get this right.
- quick performance with other measurements as well (this often doesn't show up in spec sheets, but matters in day-to-day use)
- autohold - not just the usual manual 'data' hold. Autohold is *very* useful. I think Hioki may offer this, but don't know if anyone else does.
- bar graph - very handy when watching changing signals. Some other meters provide this, some don't... but I really like having it.
- very useful min/max/average and peak min/max measurements. Some meters omit this, or leave out average or peak (transient)
- diode check will light up all LEDs and report the voltage drop. Many good meters won't do this.
- within any given measurement, an 87v will typically provide a wider range of measurement than most cheap meters
- lifetime warranty
- Proven track record of reliability, accuracy, robustness
Now the above advantages won't matter to everyone, and if they don't matter too much for what you need then a Fluke may not be worth considering. But the features above are all quite useful.
hgjdwx:
Digital multimeter has many application skills that you find.
For example, use the PEAK function to discover fleeting abnormalities.
Use Z-LOW to discharge the electrolytic capacitor.
Inline resistance measurement using a low open circuit voltage resistance range
Use AC and DC dual display multimeters (100KHZ, true RMS) to quick evaluation power quality.
Utilize the digital multimeter DCV 1uV resolution Cooperate with the pointer multimeter, fast look for the short circuit point in the circuit.
There is also the diode range of the digital multimeter. It is better to have a high open circuit voltage and high display voltage.
And it is better to show the open circuit voltage than to show the over-range "OL" on the open circuit.
Protek 223 is like this, so that it has greater flexibility to adapt to a wider range of circuit measurements.
Digital multimeter can also be combined with pointer multimeter to in-line test optocoupler
Digital multimeter DCV stable 1uV resolution is very useful.
I often use it and the pointer multimeter to find the short circuit point in the circuit, more accurate than milliohmmeter.
At this point the DT4282 does a better job. It not only has a DCV resolution of 1uV, the key is very stable.
Although other tables have a 1uV resolution, the drift is relatively large.
Attached:
To find the short circuit point in the circuit, I have a simple method.
With the pointer multimeter R*1 range and FLUKE187 DC 50mV range (resolution up to 1uV),
Method 1:
The red meter of the pointer multimeter is grounded, and the black test pen is connected to a short circuit (any point of the copper foil that is short-circuited is randomly connected).
The use of F187 50mV to measure the voltage on two direct solder joints on the copper foil. The voltage to the short-circuit point is larger (tens to hundreds of microvolts).
The voltage to the non-short circuit point is small (zero to a few microvolts). Look in the direction of the large voltage. You can quickly find the short-circuit point and you don't have to remove an extra part.
Method 2:
First, use the left hand to hold the two pens of the digital watch and contact the two adjacent solder joints on the short-circuit power line respectively.
The right hand holds the pointer table two pens, the red watch pen is grounded, and the black pen touches the two solder joints in sequence.
For two measurements, the digital meter reading must be zero at a time. There is a large reading at a time and the direction of the zero voltage is the direction of the short circuit.
Some explanations:
You don't have to use FLUKE 187. The other four and a half meters can be used.
Of course, no pointer multimeter can also be replaced with a 100mA or 1A power supply.
In fact, the operation is very simple, you only need to follow the actual sketch of my drawing, and you will immediately understand!
Interested friends can set a short-circuit point artificially, test it, is not it very convenient?
bd139:
I thought that was a stargate dialler for a minute.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version