APPA 76 User manual

RC METERPLUS
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INSTRUCTION MANUAL
APPA 76

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Introduction
1.1 Unpacking and checking
Upon removing your new RC Meterplus from its packing, you should have the following items:
1. RC meterplus.
2. Test leads set (one black and one red).
3. Operating manual.
4. Protective holster.
1.2 Front Panel
Refer to Figure 1 and the following nunberes steps to familiarize yourself with the meter’s front panel controls
and connectors.
1. Digital display — The 31⁄2 segment 1999-count digital LCD display has automatic annunciators for polarity,
decimal point, over range and low battery voltage.
2. Zero adjuster for capacitance — This allows the display to be zeroed when measuring capacitance (zeroing
range approx. ± 20pF).
3. On/off switch — Use this switch to switch the tester "ON" and "OFF".

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4. Rotary function and range switch — This switch is used to set the desired function and range.
5. Capacitance sockets — The terminals of capacitors can be inserted in these sockets to allow their capacitance
to be measured directly.
6. Capacitance input terminal (+) — Positive input for capacitance measurements. Takes banana plug.
7. Capacitance input terminal (-) — Negative input for capacitance measurements. Takes banana plug.
8. Ω, E, D, LED input terminal (+) — Positive output for testing resistors, diodes and LEDs and positive input for
battery testing. Takes banana plug.
9. Ω, E, D, LED input terminal (-) — Negative output for testing resistors, diodes and LEDs and negative input for
battery testing. Takes banana plug.
10. Transistor and SCR socket for transistors and silicon-controlled rectifiers - and for measuring transistor
hFE and ICEO and for testing SCRs.

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Figure 1

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Specifications
2.1 General specification
Display : 31⁄2 digit 1999 count LCD display.
Polarity indication : Automatic, positive implied negative indicated.
Over range : "1" or "-1"
Low battery voltage indication : "=" shown if the voltage from the battery drops below the operating voltage.
Measuring Tate : 2 times per second, nominal.
Operating temperature : 0 to +50°C, 0 to 80% RH.
Storage temperature : –20 to +60°C, 0 to 80% RH. When battery removed from meter.
Temperature coefficient : 0.15 x specified accuracy/°C, <18°C or >28°C.
Power required : Standard 9V battery, NEDA 1604, JIS 006P, IEC 6F22.
Battery life : Approx. 200 hours on alkaline battery.
Dimensions (L x B x H) : 84 x 175 x 31 mm, without holster.
95 x 192 x 50 mm, with holster.
Weight (includ battery) : 340 gms without holster
550 gms with holster
Accessories : Protective Holster, Battery and Operators Manual

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2.2 Electrical specification
Accuracy is ± (reading + number of digits) at 23°C ± 5°C, less than 75% RH.
(1) Capacitance
Range Resolution Accuracy Test frequency
200pF 0.1pF ±(0.5%rdg + 1dgt + 0.5pF)
820Hz
2nF 1pF
20nF 10pF
200nF 100pF
2µF 1nF
20µF 10nF
200µF 100nF 82Hz
2000µF 1µF ±(1%rdg + 1dgt) 8.2Hz
20mF 10µF ±(1.5%rdg + 1dgt)
±(0.5%rdg + 1dgt)

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Testing voltage : 3.2V peak (max.). The (+) socket is always positive relative to the (-) socket.
Input protection : The tester is protected against capacitor discharge (above 50V) by a 0.25A, 250V quick-acting
fuse.
Zeroing for capacitance : restricted to approx. ± 20pF
(2) Resistance
Range Resolution Accuracy Max. open circuit
voltage Overload protection
200Ω0.1Ω±(0.75%rdg + 4dgt) 3.2V
500 Vd.c./a.c. (max)
2kΩ1Ω
±(0.5%rdg + 1dgt)
20kΩ10Ω
200kΩ100Ω
2MΩ1kΩ±(0.75%rdg + 1dgt)
20MΩ10kΩ±(2%rdg + 1dgt)
0.5V

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(3) Diode testing
Range Resolution Accuracy Max. test current Max.open cuicuit
voltage
1.5mA 3.2V
1mV ±(1.5%rdg + 5dgt)
Overload protection: 500V DC/AC max.
(4) LED Test
Testing Voltage : 3.2V max.
Test Current : 2mA or 10mA two ranges.
LED lamp lighted test, display reading is LED forward voltage approx.

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(5) Transistor hFE Test, Trainsistor Leakage Iceo Test
0 - 1000 hFE values either PNP or NPN transistor
hFE Base Current : 10µA approx.
hFE Vce : 3V approx.
Iceo : 10nA - 20.00µA.
(6) SCR Test
SCR good/defect test.
(7) Battery testing
Battery type Load
9V Battery Load. 15mA approx.
1.5V AA, C or D Cell Load: approx. 150mA
1.55V Button Cells Load: approx. 0.8mA
Display reading is battery Voltage approx.

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OPERATION
3.1 Measuring capacitance
WARNING : 1. Never apply voltage to the test terminals; this could damage or destroy the tester.
2. Fully discharge capacitors before testing them.
3. With polarised capacitors, make sure they are connected with the correct polarity.
4. Do not test capacitors in-circuit.
Procedure:
1. Switch on tester (move on/off switch to "ON" position). The appearance of numbers on the LCD display
indicates the tester is on.
2. Set to the 200pF range. Adjust the zero adjuster so that the lowest digit on the display is as close as possible to
changing from "1" to "0" and the "-" sign does not appear. If you need to use test leads, plug them in before you
zero the tester. Zeroing the tester with the leads connected allows the capacitance of the leads to be nulled.
Do not short the leads together.
3. You should zero the meter whenever you are going to make measurements in order that the last digit will be as
close as possible to "0". We would remind you that the highest resolution available is on the 200pF range.

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4. If the capacitance of the capacitor you are going to measure is specified, set the appropriate range. If it is not,
start with the 200pF range. If an over range is indicated, go to the next range up. Continue doing so until the
over range annunciator disappears and a measurement is shown. This will ensure that you are using the range
offering the maximum possible resolution.
5. With low-value wire-ended capacitors and/or capacitors for PCB mounting, set the meter to "0" and insert the
capacitor terminals straight into the measuring sockets. Where it is not possible to use the measuring sockets with
the capacitors you wish to measure, plug the test leads into the (+) and (-) capacitance input terminals and apply
the leads to the capacitor terminals.
6. An over range is indicated by a "1" as the highest digit and no other digits shown.
7. The capacitance value can be read straight off the display because the meter automatically inserts the decimal
point and the range it has selected can be read off at the same time.

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Note:
1. An open-circuited capacitor will show "0" on all the ranges (expect for a few pF on the 200pF range).
2. When using the 200pF range, you are advised always to use the short test leads if the measuring socket cannot
be used in the particular case. Long test leads introduce quite large amounts of additional capacitance. If the
capacitance of the leads is more than 20pF, it will not be possible for you to null it with the zero adjuster. What is
more, even after the capacitance of the leads has been nulled, it is possible that subsequent movements of the leads
will destroy the effect of the nulling.
3. If the capacitance of the test leads is above the maximum that the zero adjuster can correct for, what you can do
is to make a note of the capacitance of the leads and subtract it from the final measurement.
4. When you wish to measure a number of capacitors some of which require the test leads and some of which do not,
you can leave the leads connected to the tester while making all of the measurements. This means that the tester
does not have to be zeroed twice (once with the leads and once without).
5. To extend the life of the battery, it is advisable for the on/off switch to be switched to "OFF" once measurements
have been completed.
6. During measurements, the tester applies a very low voltage to capacitors. With the majority of capacitors there is
no risk of their voltage limits being exceeded. Nor are the capacitors charged to dangerous voltages when they are
disconnected from the tester.

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7. Capacitors (and particularly electrolytic capacitors) are often subject to wide tolerances. Hence the values
measured are often up to 100% more than the nominal values but they are seldom drastically below them.
8. The tester uses an a.c. voltage method of measurement which is less subject to errors than the d.c. ramp
voltage method when the capacitors being measured have high leakage currents, which electrolytic capacitors
often do.
3.2 Measuring resistance
1. Switch on tester (move on/off switch to "ON" position).
2. Turn rotary switch to the desired range.
3. Plug the black test lead into the Ω"—" input terminal and the red lead into the Ω"+" input terminal.
4. Apply the probes to the points between which the resistance is to be measured and read off the value shown.
3.3 Measuring transistor hFE
1. Switch on tester (move on/off switch to "ON" position).
2. Turn rotary switch to the desired hFE range (PNP or NPN).
3. Connect the transistor straight into the transistor socket. The holes of the socket are marked E, B and C for
emitter, base and collector.
4. Read the hFE (d.c. gain) value straight off the display.

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3.4 Testing transistor leakage current (ICEO)
1. Switch on tester (move on/off switch to "ON" position).
2. Turn rotary switch to the desired ICEO range (PNP or NPN).
3. Connect the transistor straight into the transistor socket. The holes of the socket are marked E, B and C for
emitter, base and collector.
4. Read the leakage current (ICEO) of the transistor straight off the display. The unit of measurement is µA.
3.5 Testing of SCRs/ thyristors (good/bad)
1. Switch on tester (move on/off switch to "ON" position).
2. Turn rotary switch to the position SCR.
3. Insert the SCR straight into the transistor socket. The holes of the socket are marked A and G for anode and
gate and K for cathode.
4. If the SCR is good, the display should show "000".
5. Turn the rotary switch briefly to NPN hFE and back to the SCR range. If the SCR is good, the display should
now show "1" (overrange ).

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BATTERY REPLACEMENT
The tester is powered by a single 9V battery. To change the battery, refer to Fig.2 and follow the instructions given
below.
1. Remove the test leads from the component being tested, switch the tester off (move on/off switch to "OFF") and
unplug the test leads from the input terminals.
2. Lay the tester front-face-down on a work surface and unscrew the three screws in the bottom half of the case.
3. Lever up the end of the bottom half of the case closest to the LCD display until it releases from the top half with
a slight click.
4. Take the battery out of the top half of the case and carefully unplug the connector from it.
5. Press the connector onto the new battery until it clicks home and insert the battery into the top half of the case.
Make sure that the connecting wire will not be caught between the two halves of the case.
6. Fit the bottom half of the case back onto the top half. As you do so make sure that the O-rings on the case
screws are correctly seated and that the two hooked lugs are engaged in the top half. Screw the three screws
back in.

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Figure 2
Bottom half of case
Top half of case
9V Battery
Battery Connector

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FUSE REPLACEMENT
To change or check the fuse, refer to Fig.3 and follow the instructions given below.
1. Carry out steps 1 to 3 of the instructions for changing the battery.
2. Lift the printed circuit board out of the top half of the case. Do not unscrew any of the screws in the printed
circuit board.
3. Carefully remove the fuse from the fuse holder by first levering one end out of one clip and then pulling the fuse
out of the other clip.
4. Fit a new fuse of the same size with the same ratings. Make sure that the fuse is centered longitudinally in the
fuse holder.
5. Make sure that the bar of the rotary switch in the top half of the case and the rotary switch on the printed circuit
board are both in the "OFF" position.
6. Fit the printed circuit board back into its original position, making sure that O-rings on the case screws are
correctly seated and that the connecting wire of the battery will not be caught between the top and bottom
halves of the case. Fit the two halves of the case back together ensuring that the notches in the top half of the
case are engaged. Screw the three screws back in.

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Top half of case
Fuse
Fuse Holster
Bottom half of case
Fuse 0.25A, 5 x 20mm, fast blow, 250V, HBC 1.0KA Figure 3

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HOW TO USE THE PROBE HOLDER
Clip one probe on the holster for
one handed meter operation. Wrap the leads around the holster to store the test probes.

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HOW TO USE THE TILT STAND AND HOLSTER
Swing the stand out for easier meter reading. Swing the upper holder out and hook it over a door.