| Products > Test Equipment |
| Fluke 233 cut off under 20mA |
| << < (5/6) > >> |
| J-R:
--- Quote from: Fungus on April 25, 2023, 08:10:36 am --- --- Quote from: J-R on April 25, 2023, 07:55:28 am ---I do not agree with the argument that clamp meters are missing mV because they are targeted for industrial electricians. It's very hard to find this feature missing on an industrial handheld DMM. Also, many DMMs combine the mV range into the V switch position. The 87V does this for mV AC, the UT210D does this for mV DC, the U1233A does this for both AC & DC. --- End quote --- That's just Fluke protecting their 87V cash-cow. All their other meters are designed around not being a substitute for the 87V, eg. missing mV, missing uA, or whatever. They're a business and out to make as much money as possible, let's not pretend they're anything else. They're certainly not competitive or innovative any more. --- End quote --- As I pointed out, Brymen does not make a clamp meter with mV either. So Brymen is "out to make as much money as possible, let's not pretend they're anything else. They're certainly not competitive or innovative any more." There, I fixed it for you... |
| bdunham7:
--- Quote from: Fungus on April 25, 2023, 08:10:36 am ---That's just Fluke protecting their 87V cash-cow. All their other meters are designed around not being a substitute for the 87V, eg. missing mV, missing uA, or whatever. They're a business and out to make as much money as possible, let's not pretend they're anything else. They're certainly not competitive or innovative any more. --- End quote --- That line is getting tiresome. You can go to the Fluke website and read about the huge variety of innovative products that they have come out with. The fact that they continue to sell a well-regarded popular legacy product for years on end despite it not having good 'bang for buck' compared to this months Aneng special is really not that relevant to the companies overall operations. I'm sure some new person at Fluke may say "The 87V is kind of old-tech and gee, parts are getting harder to source so why don't we refresh the model?" |
| kdl1950:
Many thanks for the replies and explanations. I agree with "bduham7“ The datasheet is both technically wrong and badly misleading in this regard. It may well be true that this measuring device is not permitted in this area. Only it would have to be clearly marked in the description! The 20mA cut off is not described in the operating instructions and the service manual. If the meter only works up to 5% (300mA) AC/current, it should be „exactly“ described in the manual. And if I want to do it completely correct, the device shows "OL" below 300mA. For me the topic is closed. :palm: |
| bdunham7:
--- Quote from: kdl1950 on April 25, 2023, 04:51:59 pm ---If the meter only works up to 5% (300mA) AC/current, it should be „exactly“ described in the manual. And if I want to do it completely correct, the device shows "OL" below 300mA. --- End quote --- It is described appropriately in the fine print of the manual. And perhaps "UL" would be a better indication. I think the 'cutoff' may be a software iimplentation in this case. I tested my F116 on its 6V range and it seems that 20mV reads 21 or 22 counts but 19mV and below reads a solid 0.000. Testing on the Lo-Z 600V range, it reads down to the very low single counts, all the way to 000.1V for 100mV, however the indicator goes to 'DC' rather than 'AC' below 300mV or 3 counts. Still, it seems to have a TRMS residuum of less than 20 counts--which perhaps is just mine or perhaps they're all much lower than 20--and it still goes to zero on the 6V range. In the case of the F233, the 6A range presumably uses the 0.01R shunt, meaning full scale is 60mV, requiring a 10X gain amplifier. This may cause some noise that would be interpreted as instability or inaccuracy so they would have an additional reason to suppress it at zero. |
| AVGresponding:
--- Quote from: Fungus on April 23, 2023, 12:07:25 pm --- --- Quote from: AVGresponding on April 23, 2023, 08:19:13 am ---So readings under 300mA may or may not be accurate enough to be useful? That's quite poor, for a Fluke product. --- End quote --- That's just the way TRMS chips work. PS: Fluke sells average responding meters, too. Choose your poison. --- End quote --- You're over-simplifying (what a surprise). The ACV ranges are TRMS, use the same TRMS IC, and are better specced, and also give additional uncertainty values when outside the nominal accuracy range. |
| Navigation |
| Message Index |
| Next page |
| Previous page |