HP-90E
DIGITAL MULTIMETER
OPERATOR’S MANUAL
1.
Overview
The multimeter is characterized at slim size, portable, stable performance
and anti-dropping capacity. Using 4000 counts digit LCD monitor with
character 22mm high, they offer clear readings. With overall circuitry
design centering on large-scale IC A/D converters in conjunction and
over-load protection circuit, the meters give excellent performance and
exquisite making as a handy utility instrument.
The meters can be used to measure DC & AC voltage, DC & AC current,
resistance, capacitor, frequency, duty cycle, temperature, battery test,
positive diode voltage fall and audible continuity.
2. Panel Layout
①
LCD display: 4000 counts digit, full function symbol display.
②
SELECT key: This key work on the "
" range, press the key
to choose resistance, diode or continuity test, on the voltage or
current range, change to DC or AC; If press and hold SELECT key
to power on, “Auto Power Off ” function will be disabled.
③
HOLD
key: Press the “
HOLD
” key to lock display value, and the “
DH
”
sign will appear on the display, press it again to exit.
④
RANGE
Key: Press the “
RANGE
” key, the meter enters manual
range mode, press it more than 2 seconds again, return to auto
mode.
⑤
REL
Key: Press the “
REL
” key, the meter enters relative measuring
mode, “
REL
” is displayed on the LCD and the present reading
becomes the reference value and displayed on the display. Relative
measurement R
EL
△
=measurement value-Reference value
.
⑥
Hz/%
Key: On “ACV/ACA” or “Hz” range, press the “
Hz/%
” key, you
can choose the
Frequency
or
Duty Cycle
measurement.
⑦
CDS sensor: The CDS sensor can reaction to the ambient
brightness range, then automatically control the LCD backlight
to lighten or go out.
⑧
Rotary Switch: use this switch to select functions and ranges.
⑨
VHz
Input Jack
⑩
COM and Temperature “-” Input Jack
⑪
μAmA/BATT and Temperature “+” Input Jack
⑫
20A Input Jack
3. Safety Information
3-1 The meters are designed according to IEC-1010 concerning electronic
measuring instruments with an over-voltage category 600V (CAT
Ⅳ
) and
pollution 2.
3-2 Follow all safety and operating instructions to ensure that the meter is
used safely and is kept in good operating condition.
3-3 safety symbols:
Important safety information, refer to the operating manual.
Dangerous voltage may be presence.
Double insulation (protection Class II)
4. Special Cautions for Operation
4-1 The meters can be safe only according to standard procedures when
used in conjunctions with the supplied test leads. To replace damaged test
leads with only the same model or same electric specifications.
4-2 To avid risk of electric shock, do not use the meters before the cover is
in place.
4-3 The range switch should be right position for the testing.
4-4 To avoid electric shock and damaging the instruments, the input
signals are forbidden to exceed the specified limits.
4-5 When measuring TV set or switched power, attention should be paid to
the possible pulses that may bring destruction to the circuit.
4-6 Range switch position is forbidden to be changed at random during
measurement.
4-7 Take caution against shock in the course of measuring voltage higher
than DC 60V & AC 30V.
4-8 Protection fuse should be replaced only with same type and same
specification.
4-9 After operation is finished, set function switch at OFF range to save
battery power.
4-10 If the meter is without usage for long time, take out battery to avoid
damage by battery leakage.
5. GENERAL SPECIFICATIONS
5-1 Max Voltage between input terminal and Earth Ground: CAT
Ⅳ
600V
5-2 Over-range Indication: display “OL” for the significant digit.
5-3 Automatic display of negative polarity “-” .
5-4 Low Battery Indication: “ ” displayed.
5-5 Max LCD display: 4000 counts digit.
5-6 Auto range & Manual range control
5-7 Auto Power Off: When measurement exceeds 30 minutes without
switching mode and pressing key, the meter will switch to standby
mode. Press any key to exit standby mode. When restart the system,
press and hold
SELECT
key to disable auto power off.
5-8 Auto LCD backlight
5-9 Fuse protection: 400mA/250V PPTC Resettable Fuse
F-20A/250V Fuse (Ø5x20mm)
5-10 Power supply: 9V battery (6F22)
5-11 Operating Temp.: 0
℃
to 40
℃
(relative humidity <85%)
5-12 Storage Temp.:-10
℃
to 50
℃
((relative humidity <85%)
5-13 Guaranteed precision Temp.: 23
±
5
℃
(relative humidity <70%)
5-14 Dimension: 193x88x41mm
5-15 Weight: approx. 320g (including battery)
6. Testing Specifications
Accuracy is specified for a period of year after calibration and at 18
℃
to
28
℃
(64
℉
to 82
℉
) with relative humidity to 70%.
6-1 DC Voltage
Range
Resolution
Accuracy
400mV
0.1mV
±(0.5% of rdg + 2 digits)
4V
1mV
40V
10mV
400V
100mV
1000V
1V
±(0.8% of rdg + 2 digits)
-- Impedance: 10MΩ, More than 100MΩ on 400mV range
-- Overload protection: 250V DC or AC rms for 400mV range, effective
1000V DC or 750V AC rms for other ranges
6-2 AC Voltage
Range
Resolution
Accuracy
400mV
0.1mV
±(1.2% of rdg + 3 digits)
4V
1mV
±(0.8% of rdg + 3 digits)
40V
10mV
400V
100mV
750V
1V
±(1.2% of rdg + 3 digits)
--The 400mV range be selected by press “
RANGE
” key only
-- Impedance: 10MΩ, More than 100MΩ on 400mV range
-- Overload protection: 250V DC or AC rms for 400mV range, effective
1000V DC or 750V AC rms for other ranges
-- Frequency Range: 40 to 400Hz
-- Response: average, calibrated in rms of sine wave
6-3 DC Current
Range
Resolution
Accuracy
4
00μA
0.1
μA
±(1.2% of rdg + 2 digits)
4
000μA
1
μA
40mA
10
μA
400mA
100
μA
4A
1mA
±(2.0% of rdg + 3 digits)
20A
10mA
-- Overload protection: 400mA/250V PPTC Resettable Fuse
F-20A/250V Fuse, 20A up to 10 seconds
6-4 AC Current
Range
Resolution
Accuracy
4
00μA
0.1
μA
±(1.5% of rdg + 3 digits)
4
000μA
1
μA
40mA
10
μA
400mA
100
μA
4A
1mA
±(2.5% of rdg + 5 digits)
20A
10mA
-- Overload protection: 400mA/250V PPTC Resettable Fuse
F-20A/250V Fuse, 20A up to 10 seconds
-- Frequency Range: 40 to 400Hz
-- Response: average, calibrated in rms of sine wave
6-5 Resistance
Range
Resolution
Accuracy
4
00Ω
0.1Ω
±(1.0% of rdg + 3 digits)
4
kΩ
1Ω
±(1.0% of rdg + 2 digits)
4
0kΩ
10Ω
4
00kΩ
100Ω
4
MΩ
1kΩ
4
0MΩ
10k
Ω
±(1.5% of rdg + 3 digits)
-- Overload protection: 250V DC or AC rms
