1.6 General Safety Information......................................................................... 1-4
1-1
1.1 Introduction
Read these pages carefully before beginning to install and use the instrument.
The following paragraphs contain information, cautions and warnings which must be
followed to ensure safe operation and to keep the instrument in a safe condition.
Servicing described in this manual is to be done only by
qualified service personnel. To avoid electrical shock, do not
service the instrument unless you are qualified to do so.
1.2 Safety Precautions
For the correct and safe use of this instrument it is essential that both operating and
service personnel follow generally accepted safety procedures in addition to the safety
precautions specified in this manual. Specific warning and caution statements, where
they apply, will be found throughout the manual. Where necessary, the warning and
caution statements and/or symbols are marked on the instrument.
Warning
Safety Instructions
1.1 Introduction
1
1.3 Caution and Warning Statements
Caution
Used to indicate correct operating or maintenance procedures
to prevent damage to or destruction of the equipment or other
property.
Warning
Calls attention to a potential danger that requires correct
procedures or practices to prevent personal injury.
1.4 Symbols
Table 1-1 shows the symbols used on the test tool or in this manual.
Table 1-1. Symbols
Read the safety information in the Users
Manual
Equal potential inputs, connected
internally
Live voltageRecycling information
DOUBLE INSULATION (Protection Class)
Static sensitive components
(black/yellow).
EarthDisposal information
Conformité Européenne
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1.5 Impaired Safety
1.6 General Safety Information
Whenever it is likely that safety has been impaired, the instrument must be turned off
and disconnected from line power. The matter should then be referred to qualified
technicians. Safety is likely to be impaired if, for example, the instrument fails to
perform the intended measurements or shows visible damage.
Warning
Removing the instrument covers or removing parts, except
those to which access can be gained by hand, is likely to
expose live parts and accessible terminals which can be
dangerous to life.
The instrument shall be disconnected from all voltage sources before it is opened.
Capacitors inside the instrument can hold their charge even if the instrument has been
separated from all voltage sources.
Components which are important for the safety of the instrument may only be replaced
by components obtained through your local FLUKE organization. These parts are
indicated with an asterisk (*) in the List of Replaceable Parts, Chapter 8.
The Fluke 43B has been designed and tested in accordance with Standards ANSI/ISA
S82.01-1994, EN 61010.1 (1993) (IEC 1010-1), CAN/CSA-C22.2 No.1010.1-92
(including approval), UL3111-1 (including approval) Safety Requirements for
Electrical Equipment for Measurement, Control, and Laboratory Use.
This manual contains information and warnings that must be followed by the user to
ensure safe operation and to keep the instrument in a safe condition. Use of this
equipment in a manner not specified by the manufacturer may impair protection
provided by the equipment.
Performance Characteristics
FLUKE guarantees the properties expressed in numerical values with the stated
tolerance. Specified non-tolerance numerical values indicate those that could be
nominally expected from the mean of a range of identical ScopeMeter test tools.
Environmental Data
The environmental data mentioned in this manual are based on the results of the
manufacturer’s verification procedures.
Characteristics
2.1 Introduction
2
2.2 Safety Specifications
Safety Characteristics
Designed and tested for measurements on 600 Vrms Category III, Pollution Degree 2
in accordance with:
• EN 61010.1 (1993) (IEC 1010-1)
• ANSI/ISA S82.01-1994
• CAN/CSA-C22.2 No.1010.1-92 (including approval)
• UL3111-1 (including approval)
Installation Category III refers to distribution level and fixed installation circuits
inside a building.
Maximum input voltage Input 1 and 2
Direct on inputs or with test leads TL24 ............................................... (see Figure 2-1)
0 to 66 kHz ................................................................................................. 600 Vrms
> 66 kHz ....................................................................................... derating to 5 Vrms
With Shielded Banana-to-BNC Adapter Plug BB120 ...........................(see Figure 2-1)
0 to 400 kHz ............................................................................................... 300 Vrms
> 400 kHz ..................................................................................... derating to 5 Vrms
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Figure 2-1. Max. Input Voltage vs. Frequency
Maximum floating voltage
From any terminal to ground
0 to 400 Hz ................................................................................................. 600 Vrms
2.3 Function Specifications
The accuracy of all measurements is within ± (% of reading + number of counts) from
18 °C to 28 °C. For all specifications, probe specifications must be added.
2.3.1 Electrical functions
Specifications are valid for signals with a fundamental between 40 and 70 Hz.
Minimum input voltage ................................................................................. 4 V peak-peak
Minimum input current............................................................... 10 A peak-peak (1 mV/A)
Input bandwidth................................................ DC to 15 kHz (unless specified otherwise)
excluding test leads or probes ................................................DC to 20 MHz (-3 dB)
with test leads TL24 .................................................................DC to 1 MHz (-3 dB)
with 10:1 probe VPS100-R (optional).................................... DC to 20 MHz (-3 dB)
with shielded test leads STL120 (optional)......................... DC to 12.5 MHz (-3 dB)
DC to 20 MHz (-6 dB)
Lower transition point (ac coupling).................................................... 10 Hz (-3 dB)
Bandwidth input 2 (current)
with Banana-to-BNC adapter ...............................................................DC to 15 kHz
Lower transition point (ac coupling).................................................... 10 Hz (-3 dB)
Scope readings
The accuracy of all scope readings is valid from 18 °C to 28 °C with relative humidity
up to 90 % for a period of one year after calibration. Add 0.1 x (the specified
accuracy) for each °C below 18 °C or above 28 °C. More than one waveform period
must be visible on the screen.
V dc, A dc ........................................................................................ ±(0.5 % + 5 counts)
V ac and V ac+dc (True RMS) input 1
DC to 60 Hz................................................................................. ±(1 % + 10 counts)
60 Hz to 20 kHz........................................................................ ±(2.5 % + 15 counts)
The Fluke 43B, including standard accessories, conforms with the EEC directive 89/336
for EMC immunity, as defined by IEC1000-4-3, with the addition of the following tables.
Disturbance with test leads TL24 or Current Clamp 80i-500s
• Volts / amps / hertz
• Resistance, Capacitance
• Power
• Harmonics
Table 2-1. No Visible Disturbance
No visible disturbanceE = 3 V/mE = 10 V/m
Frequency: 10 kHz - 27 MHz
Frequency: 27 MHz - 1 GHz
(-)
(-)
(-): no visible disturbance
Disturbance with test leads TL24 in scope mode
• V ac+dc (True RMS)
Table 2-2. Disturbance < 1 %
Disturbance less than 1 %
of full scale
Frequency: 10 kHz - 27 MHz
Frequency: 27 MHz - 200 MHz
Frequency: 200 MHz - 1 GHz
E = 3 V/mE = 10 V/m
2 V/div - 500 V/div
500 mV/div - 500V/div
(-)
(-): no visible disturbance
Table 2-3. Disturbance < 10 %
Disturbance less than 10 %
of full scale
Frequency: 10 kHz - 27 MHz
Frequency: 27 MHz - 200 MHz
E = 3 V/mE = 10 V/m
1 V/div
200 mV/div
(-)
(-)
10 V/div - 500 V/div
2 V/div - 500 V/div
5 mV/div - 500 V/div
5 V/div
1 V/div
2-10
Frequency: 200 MHz - 1 GHz
(-)
(-)
(-): no visible disturbance
Ranges not specified in Tables 2 and 3 may have a disturbance of more than 10 % of full
scale.
3.3.4 Digital Circuit ...................................................................................... 3-24
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3-2
Figure 3-1. Fluke 43B Block Diagram
ST7965.EPS
3.1 Introduction
Section 3.2 describes the functional block diagram shown in Figure 3-1. It provides a
quick way to get familiar with the test tool basic build-up.
Section 3.3 describes the principle of operation of the test tool functions in detail, on the
basis of the circuit diagrams shown in Figures 9-1 to 9-5.
For all measurements, input signals are applied to the shielded input banana jackets.
Traces and readings are derived from the same input signal samples.
3.2 Block Diagram
In the block diagram Figure 3-1, the test tool is divided in five main blocks. Each block
represents a functional part, build up around an Application Specific Integrated Circuit
(ASIC). A detailed circuit diagram of each block is shown in Section 9.
Table 3-1 provides an overview of the blocks in which the test tool is broken down, the
main block function, the ASIC name, and the applicable circuit diagram.
Circuit Descriptions
3.1 Introduction
3
Table 3-1. Fluke 43B Main Blocks
BlockMain FunctionsASICCircuit
Diagram
INPUT 1Input 1 signal conditioningC(hannel)-ASIC OQ0258Figure 9-1
INPUT 2Input 2 signal conditioningC(hannel)-ASIC OQ0258Figure 9-2
TRIGGERTrigger selection and conditioning
Current source for resistance, capacitance,
continuity, and diode measurements
AC/DC input coupling and Ω/F relay control
Voltage reference source
DIGITALAnalog to Digital Conversion
Acquisition of ADC samples
Micro controller (µP-ROM-RAM)
Keyboard- and LCD control
POWERPower supply, battery charger
LCD back light voltage converter
Optical interface input
T(rigger)-ASIC OQ0257Figure 9-3
D(igital)-ASIC MOT0002Figure 9-4
P(ower)-ASIC OQ0256Figure 9-5
All circuits, except the LCD unit and the KEYBOARD, are located on one Printed
Circuit Board (PCB), called the MAIN PCB.
The ASIC’s are referred to as C-ASIC (Channel ASIC), T-ASIC (Trigger ASIC), P-ASIC
(Power ASIC), and D-ASIC (Digital ASIC).
3.2.1 Input 1 - Input 2 Measurement Circuits
The basic input signal for the Input 1 and Input 2 circuits (hardware) is voltage. The
reading of Input 1 is in (milli)Volts. The reading of Input 2 is in Amperes. So the
voltage on Input 2 is assumed to be supplied by a current clamp. From the measured
voltage samples the readings are calculated by the instrument firmware. For example:
power readings are calculated from the Input 1 and Input 2 voltage samples.
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The Input 1 and Input 2 measurement circuits are partially identical. The differences are:
• Only Input 1 provides facilities for Ohms, Continuity, Diode, and Capacitance
measurements.
• The bandwidth of the Input 1 circuit is 20 MHz, the bandwidth of Input 2 is 15 kHz.
• Input 2 has an additional hum rejection circuit.
The circuit description below applies to the Input 1 and Input 2 circuit.
Input 1 and Input 2 measurement principle
An input voltage applied to Input 1 or Input 2 is supplied to the C-ASIC via the HF path
(Input 1 only) and the LF path. Depending on the actual measurement function the
Input-1 HF path in the C-ASIC is enabled or disabled. The HF DECade ATTenuator and
LF DECade ATTenuator are external components for the HF and LF path. The C-ASIC
converts (attenuates, amplifies) the input signal to a normalized output voltage
ADC-A/ADC-B, which is supplied to the Analog to Digital Converters (ADC-A and
ADC-B) on the DIGITAL part. The D-ASIC acquires the digital samples to build the
traces, and to calculate readings.
For the electrical functions the current Input 2 circuit is operating in low voltage ranges.
For example a current of 10A measured with a 1 mV/A current clamp generates 10 mV
(voltage range 10 mV/div). To minimize the influence of interference voltages, Input 2
has no HF path, and has an additional hum reject circuit.
The lowest Input 1 voltage range for electrical measurements is 4V/div, which is high in
comparison with the Input 2 range.
Ohms, Continuity, and Diode measurement function (Input 1 only)
The T-ASIC supplies a current via the Ω/F relays to the unknown resistance Rx or diode
connected to the Input 1 and the COM input jacket. The voltage drop across Rx or the
diode is measured according to the Input 1 measurement principle.
Capacitance measurement function (Input 1 only)
The T-ASIC supplies a current via the Ω/F relays to the unknown capacitance Cx,
connected to the Input 1 and the COM input jacket. Cx is charged and discharged by this
current. The C-ASIC converts the charging time and the discharging time into a pulse
width signal. This signal is supplied to the T-ASIC via the C-ASIC trigger output
TRIG-A. The T-ASIC shapes and levels the signal, and supplies the resulting pulse
width signal ALLTRIG to the D-ASIC. The D-ASIC counts the pulse width and
calculates the capacitance reading.
Scope measurement function
In the Scope measurements function the test tool shows the traces and readings derived
from the input signals. The Input 1 HF path is enabled, which results in a 20 MHz
bandwidth. The Input 2 bandwidth is 15 kHz.
Other measurement functions
Volts/Amperes/Hertz (LF), Power (LF), Harmonics (LF), Sags & Swells (LF),
Transients, Inrush Current (LF), and Temperature measurement results are calculated
from acquired input voltage samples. For functions with (LF), the HF path of Input 1 is
disabled, which results in a 15 kHz bandwidth for both Input channels.
3-4
Miscellaneous
Control of the C-ASIC, e.g. selecting the attenuation factor, is done by the D-ASIC via
the SDAT and SCLK serial communication lines.
An offset compensation voltage and a trace position control voltage are provided by the
D-ASIC via the APWM bus.
The C-ASIC’s also provide conditioned input voltages on the TRIG-A/TRIG-B line. One
of these voltages will automatically be selected as trigger source by the T-ASIC.
3.2.2 Trigger Circuit
The T ASIC selects one of the possible trigger sources TRIG-A (Input 1) or TRIG-B
(Input 2). For triggering on transients the selected trigger source signal is processed via
the high pass Trigger Filter (TVOUT-TVSYNC lines). Two adjustable trigger levels are
supplied by the D-ASIC via the PWM FILTERS (TRIGLEV1 and TRIGLEV2 line).
Depending on the selected trigger conditions (- source, - level, - edge, - mode), the
T-ASIC generates the final trigger signal TRIGDT, which is supplied to the D-ASIC.
The TRIG-A input is also used for capacitance measurements (see Section 3.2.1).
The T-ASIC includes a constant current source for resistance and capacitance
measurements. The current is supplied via the GENOUT output and the Ω/F relays to
the unknown resistance Rx or capacitance Cx connected to Input 1. The SENSE signal
senses the voltage across Cx and controls a CLAMP circuit in the T-ASIC. This circuit
limits the voltage on Input 1 at capacitance measurements. The protection circuit
prevents the T-ASIC from being damaged by voltages supplied to the input during
resistance or capacitance measurements.
Circuit Descriptions
3.2 Block Diagram
3
The T-ASIC contains opamps to derive reference voltages from a 1.23 V reference
source. The gain factors for these opamps are determined by resistors in the REF GAIN
circuit. The reference voltages are supplied to various circuits.
The T-ASIC also controls the Input 1/2 AC/DC input coupling relays, and the Ω/F relay.
Control data for the T-ASIC are provided by the D-ASIC via the SDAT and SCLK serial
communication lines.
3.2.3 Digital Circuit
The D-ASIC includes a micro processor, ADC sample acquisition logic, trigger logic,
display and keyboard control logic, I/O ports, and various other logic circuits.
The instrument software is stored in the 8M FlashROM; the 4M RAM is used for
temporary data storage.
For Voltage and Resistance measurements, the conditioned Input 1/2 voltages are
supplied to the ADC-A and ADC-B ADC. The voltages are sampled, and digitized by
the ADC’s. The output data of the ADC’s are acquired and processed by the D-ASIC.
For capacitance measurements the pulse width of the T-ASIC output signal ALLTRIG,
which is proportional to the unknown capacitance, is counted by the D-ASIC.
The DPWM-BUS (Digital Pulse Width Modulation) supplies square wave signals with a
variable duty cycle to the PWM FILTERS circuit (RC filters). The outgoing
APWM-BUS (Analog PWM) provides analog signals of which the amplitude is
controlled by the D-ASIC. These voltages are used to control e.g. the trace positions
(C-ASIC), the trigger levels (T-ASIC), and the battery charge current (P-ASIC).
In random sampling mode (Scope mode time base faster than 1 µs/d), a trace is built-up
from several acquisition cycles. During each acquisition, a number of trace samples are
placed as pixels in the LCD. The RANDOMIZE circuit takes care that the starting
moment of each acquisition cycle (trigger release signal HOLDOFF goes low) is random.
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This prevents that at each next acquisition the trace is sampled at the same time
positions, and that the displayed trace misses samples at some places on the LCD.
The D-ASIC supplies control data and display data to the LCD module. The LCD
module is connected to the main board via connector X453. It consists of the LCD, LCD
drivers, and a fluorescent back light lamp. As the module is not repairable, no detailed
description and diagrams are provided. The back light supply voltage is generated by the
back light converter on the POWER part.
The keys of the keyboard are arranged in a matrix. The D-ASIC drives the rows and
scans the matrix. The contact pads on the keyboard foil are connected to the main board
via connector X452. The ON-OFF key is not included in the matrix, but is sensed by a
logic circuit in the D-ASIC, that is active even when the test tool is turned off.
Via the PROBE-A and PROBE-B lines, connected to the Input 1 and Input 2 banana
shielding, the D-ASIC can detect if a probe is connected.
The D-ASIC sends commands to the C-ASICs and T-ASIC via the SCLK and SDAT
serial control lines, e.g. to select the required trigger source.
Various I/O lines are provided, e.g. to control the BUZZER and the Slow-ADC (via the
SADC bus).
3.2.4 Power Circuit
The test tool can be powered via the power adapter, or by the battery pack.
If the power adapter is connected, it powers the test tool and charges the battery via the
CHARGER-CONVERTER circuit. The battery charge current is sensed by sense
resistor Rs (signal IBAT). It is controlled by changing the output current of the
CHARGER-CONVERTER (control signal CHAGATE).
If no power adapter is connected, the battery pack supplies the VBAT voltage. The
VBAT voltage powers the P-ASIC, and is also supplied to the FLY BACK
CONVERTER (switched mode power supply).
If the test tool is turned on, the FLY BACK CONVERTER generates supply voltages for
various test tool circuits.
The +3V3GAR supply voltage powers the D-ASIC, RAM and ROM. If the test tool is
turned off, the battery supplies the +3V3GAR voltage via transistor V569. This
transistor is controlled by the P-ASIC. So when the test tool is turned off, the D-ASIC
can still control the battery charging process (CHARCURR signal), the real time clock,
the on/off key, and the serial RS232 interface (to turn the test tool on).
To monitor and control the battery charging process, the P-ASIC senses and buffers
battery signals as temperature (TEMP), voltage (BATVOLT), current (IBAT).
Via the SLOW ADC various analog signals can be measured by the D-ASIC. Involved
signals are: battery voltage (BATVOLT), battery type (IDENT), battery temperature
(TEMP), battery current (BATCUR) LCD temperature (LCDTEMP, from LCD unit),
and 3 test output pins of the C-ASIC’s, and the T-ASIC (DACTEST). The signals are
used for control and test purposes.
3-6
The BACK LIGHT CONVERTER generates the 400V ! supply voltage for the LCD
fluorescent back light lamp. If the lamp is defective a 1.5 kV voltage can be present for
0.2 second maximum. The brightness is controlled by the BACKBRIG signal supplied
by the D-ASIC.
Serial communication with a PC or printer is possible via the RS232 optically isolated
interface. The P-ASIC buffers the received data line (RXDA) and supplies the buffered
data (RXD) to the D-ASIC. The transmit data line TXD is directly connected to the
D-ASIC.
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