Hi guys
Here is finally my full review about the Hioki DT4281.
I used this meter now for almost five month and was most of the time very happy with my Hioki, special because the measure results are so stable.
First I'll write a bit about the meters housing/body. Second I'll write a bit about the buttons/functions. Third a bit about the measure function itself.
About the body/housing:I think the first thing I noticed when I got this meter how thick and wide it is. But it never thought “it is to wide” or “it's to thick”. I also can keep it in my hand, so no problem with the size. But it's clearly on the larger side from what I like.
About the ruggedness, it's clearly not the toughest meter I know, but it will survive everyday in the field. Meters in this size and wight become all a bit less rugged and the Hioki really has really just a bit of rubber on the sides and a bit on the back, .. really just enough, not more.
Like almost all meter there is no rubber on the back, so if work in the field and put the meter on something it might slip away, just like others.
The stand works very well and the meter is very stable by using it. There are also all Power-On options printed on the backside.
The range switch feels very good. Even by trying to set to position between two ranges, the range switch goes by himself left or right in a proper position. Of course it's possible to set the switch between but you really have to wanna do it and even the (like me, I just tried again) you need three or four times to try. Just one thing here. The range switch stand up from the front.
The sockets for the test leads. I guess they are almost a bit to much resisted because of the safety mechanism (closing the A and mA socket. But I never had any problem with the sockets/test leads (never a test lead felt off by accident or so). I just noticed the test leads make contact when the plug almost full is in the socket and not like other on other meters when they'r half out.
There is an second point I dislike on the plugs. I like to have my leads plugged in with the leads go over the meter and leave on the left side. If I do this on the Hioki, the leads almost run over the range switch because of the short distance between the sockets and the range switch.
The display is very good. Brightness, contrast like on new Fluke 170s (a bit brighter than Agilent's U1272a). Also to see the digits from left, right, top or bottom side no problem at all. The backlight is white and very bright. There are no bright or dark spots at all. There is also a red backlight for the indication from overvoltage/current and continuity (more about the red backlight later).
I never use any from these clips the backside from multimeters to store the test leads. I think the clips on the DT 4281 are not the best, but because I anyway never use I don't care at all (I just tried now to write it here in this review).
About the buttons and the functions:The DT428x series meters have no menu like much some other meter in the top range. All setting are done with Power-On functions (printed on the stand
) and it all works perfect (ref. Impedance for dBm, 0-20/4-20mA, beeper, clear all memory).
MIN/MAX
Unlike on other meters the Min/Max function is always working in the background. To reset Min/Max there is a CLEAR button just next to the Min/Max button. I very like this feature and the implementation much. Often I like to see a Min or a Max value for each cycle from a machine or something. So I can set the display to Min or Max at display the value. To reset I just have to push the clear button after each cycle. On the display, there is still always the the Min or Max value
. Usually on other meters you have to leave the Min/Max mode, start Min/Max mode again and set the display to Min or Max. On the other side the DT428x does not have AVERAGE.
RELATIVE (delta, zero, null)
Starting relative measurements is just an secondary function on this meter. To start you have to push long on the MIN/MAX button. I don't use this often, so no problem for me. Some other people would like to have this as an primary function, like it is on almost all other meters. More bothers me, it is not possible to set a value as reference catched with AUTOHOLD function.
CLEAR
This button is to reset the MIN/MAX and PEAK function and to clear single stored values.
READ
Load and show stored values. The function jumps over deleted values.
FILTER
To filter higher out higher frequencys in V AC and in V AC+DC mode
BACKLIGHT
Turn the backlight on for about 30s. It's also possible to disable the backlight auto off with a Power-On function (it save the setting, not an single time function).
RANGE/AUTORANGE
The function is like on every meter. But … by setting the range manual, the range is showed on the main display and disappears after about half a second. So there is no visual info about the actual range. If the voltage is higher than the range (manual/ auto just over max voltage) the display turn red. So even with backlight on there is an visual indication. You can like it or not …
HOLD/AUTOHOLD
Works well, does autorange in this mode too. Sadly no values can be used for relative
. But the values can be stored.
MEM
Save values. With the cursor buttons it is possible to choose the memory number / storage place. Very easy to use.
SLOW
Set the display rate to 1 time per second and does average the values. So on a slow PWM signal from for example on a heating element, the showed value is pretty stable and close to the calculated value. On the Hioki the function is way better implemented than the “Smooth” function on my Agilent U1272a.
PEAK VOLT/AMPERE
Does not autorange. Fixed to 18,180,1500V AC/ 6,60,600,1000V DC/ 6,60,600,1000V AC+DC// 1200,12000uA /120,1200mA
Always both Peak Max and Min values showed on the display on the same time.
So, now the most important part. How does the meter his main job, how does it measure?In short … it does everything very, very well. Very stable, repetitive and rock solid readings, no flickering last digits. The meter just give you the feeling:“You can trust me”.
But also here a bit more about each function.
V AC/ dBm/ dBV/ Current clampDoes autorange from 60,000mV AC to 1000,0 V AC on the same range position and always show the voltage and the frequency. I don't remember exactly on how low the frequency is correct showed. I just remember it was a bit lower than on the Agilent U1272a. The reading is fast and stable.
In all voltage ranges the display turns red as soon the voltage is larger than the range (in each range if manual, just over 1000V in auto).
The dBm/ dBV in never really used.
The current clamp function is one thing Hioki really fucked up on this meter.
First just in AC, not DC and AC+DC.
Second, even Hioki itself has has clamps and rogowski coils with 1,10,100,1000A to 1,10,100mV ratio, Hioki also has also three (just) AC clamps with other ratios and this meter is just build for this three exotic clamps
. It is possible to cheat the ratio so it does match to my clamp, but my clamp has a much higher ranges than these three small Hioki clamps. So soon the display turn red and does show overcurrent, but no value. I really don't understand this. Special because most Hioki's clamps and rogowski coils does not match tho this meter with these ratios and overcurrent settings.
Of course I can use my clamp without this mV to A recalculate function, but it would be much nicer with ...
V DCDoes autorange from 60,000mVDC to 1000,0 VDC. Does it fast and stable. Because it has a higher input impedance on the mV range it often is switching between 600mV and 6V range in the field with nowhere connected leads. So there is just a dot moving on the display. But so it is with two different impedances. With autorange it is probably the fastest meter I know, in manual range from 0 to 20V it is about the same as a Fluke 170 in manual range.
V AC+DCDoes autorange from 6,0000 V to 1000,0 V. Like on the other voltage functions, 5x display update per second. Does show voltage and frequency at the same time. Does everything well and stable.
Continuity and Diode testOn the continuity check you can easy and always set the threshold value by the cursor buttons on the right side to 20,50,100,500 Ohm. The beep is fast like on a Fluke and the red backlight start to light up (solid, not blinking). So even with with the backlight on there is an clear a different visual signal. After release there is no backlight, if there was no before, or there is the white backlight again, if there was the backlight was on before (on the Agilent is always the backlight off after).
Diode testHere is also easy to set the treshold just by the cursor buttons from 0.15, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0V and it can measure up to 3.6V. If the voltage is lower on a diode, or a short, the display also turns red.
OhmVery fast, very stable. 60.000Ohm-6.000MOhm, 60.00MOhm, 600.0MOhm
The Fluke 170 is a bit faster by shorting the shorting the leads but also misses two ranges (600MOhm, 60Ohm).
TemperatureJust one update per second, but that's mostly ok. The reading are about the same as other Flukes, just my Agilent is about 1 °C lower.
CapacityOn some ranges it is not the fasted meter to measure capacity, but it is clearly not a slow meter. But also here … if there is a value on the display, the value is stable, no settling … repetitive.
Ranges from 1.000nF to 100.0mF.
But to be honest, I almost never used this meter to measure caps, so I tried just a bit lately, so I don't have to write “I never used”.
uA/ mAStart in DC, change with the SHIFT to AC but not to AC + DC. On AC currents there is also the frequency showed. In the mA range, there is also the 0/4-20mA function. Shows the percentage xx.xx% from 0/4-20mA.
So... I hope I forgot not to much ...
ConclusionOf course the meter is a bit on the higher price side, but for me it was worth it and I never did it regret. The DT4281 is very easy to use but on the other side it has less functionality than some other meter in this price range.
Some people write on the forum “the Hioki has specs like a 289”. But even they may have similar specs, they are very different kind of meters. The DT428x are much more meters like the 87V.
There are just two points who bother my on the meter a bit. You can't take a value from HOLD to RELATIVE (zero, delta) and the other thing with the clamp ratio. I also wish next time they would make it possible to use a clamp ratio in all voltage ranges (DC,AC+DC).
Finally I have to say the big shiny point is the not just fast (just soso fast for capacity) and also very stable and repetitive reading in all ranges. I wrote now many lines of text but the last sentence is the most important here and really thumbs up
You can easy use all function without lookup howtodo in the manual.
Oh one thing … after the meter did AutoPowerOff, you cannot restart it by pushing a button, you have to turn the range switch off and on again. If you are in any A range you have to remove the test lead because of the shutter... also not so good. But at least the meter does beep 5 or 10 seconds before it shut down.
greetings