Fluke 893A User manual

'^;v ;I
T. 033A1-12-989-4
VOLTMETER, ELECTRONiC
MODEL 893A/AC
CONTRACT NO. F41608-74-D-175€
JOHN FLUKE mfg. co., inc

JOHN FLUKE MFG.CO,, INC.
RO. Box 43210
Mountiake Terrace,Washington 98043
T. 033AM2-989-4
VOLTMETER, ELECTRONIC
MODEL 893A/AC
CONTRACT NO. F41608-74-D-1756

The JOHN FLUKE MFC, CO., INC.* warrants each instrument manufactured by them to be free from defects in material and workmanship.
Their obligation under this Warranty is limited to servicing or adjusting an instrument returned to the factory for that purpose, and to making
good at the factory any part or parts thereof; except tubes, fuses, choppers and batteries, which shali, within one year after making delivery to
the original purchaser, be returned by the original purchaser with transportation charges prepaid, and which upon their examination shall dis-
close To their satisfaction to have been thus defective, (f the fault has been caused by misuse or abnormal conditions of operations, repairs wiii
be billed at anominal cost, in this case, an estimate will be submitted before work is started, if requested.
If any fault develops, the following steps should be taken;
1.Notify the John Fluke Mfg. Co., Inc.,* giving full details of the difficulty, and include the Mode! number, type number, and serial
number. On receipt of this information, service data or shipping instructions wilt be forwarded to you.
2. On receipt of the shipping instructions, forward the instrument prepaid, and repairs will be made at the factory, if requested, an
estimate wiil be made before the work begins, provided the instrument is not covered by the Warranty.
“The foregoing warranty is in lieu of all other warramies, express or implied, including but not limited
to, any implied warranty of merchantability, fitness or adequacy for any particular purpose or use.
Fluke shall not be liable for any special, incident or consequential damages."
SHIPPING
Ail shipments of John Fluke Mfg. Co., Inc.* instruments should be made via United Parcel Service or "Best Way"* *prepaid. The instrument
should be shipped in the original packing carton; or if it is not available, use any suitable container that is rigid. If asubstitute container is used,
the instrument should be wrapped in paper and surrounded with at least four inches of excelsior or similar shock-absorbing material.
CLAIM FOR DAMAGE IN SHIPMENT
The instrument should be thoroughly inspected immediately upon receipt. All material in the container should be checked against the enclosed
packing list. The manufacturer will not be responsible for shortages against the packing sheet unless notified immediately, If the instrument
fails to operate properly, or is damaged in any way. aclaim should be filed with the carrier. Afull report of the damage should be obtained
by the claim agent, and this report should be forwarded to John Fluke Mfg. Co., Inc.* Upon receipt of this report, you will be advised of the
di^osition of the equipment for repair or repiecement. Include the model number, type number, and serial number when referring to this
instrument for any reason.
The John Fluke Mfg. Co.. Inc.* will be happy to answer all application questions which will enhance your use of this instrument. Please ad-
dress your requests to; JOHN FLUKE MFG. CO,, INC., P. O. Sox 7428, SEATTLE, WASHINGTON 98133*.
*For European customers: FLUKE (Nederland) B.V.
Ledeboerstraat 27
Tilburg, Netherlands
**For European customers. Air Freight prepaid,
FLUKE TECHNICAL SERVICE CENTERS
Fluke Western Technical Center
Mike Nagy, Service Manager
2020 North Lincoln St.
Burbank, CA 91504
Tei. 213-849-4641
TWX: 910-497-2086
Fluke Western Technical Center
Tom Marshall, Service Manager
4805 Mercury St.
San Diego, CA 92111
Tel. [phone]
TWX: 910-337-1273
Fluke Western Technical Center
Attn; Tom Marshall
2359 De La Cruz Blvd
Santa Clara, CA 95050
Tei. 408-244-1505
TWX: 910-338-0121
Fluke S.W. Technical Center
Mel Sueizie, Service Manager
Unit 4
1980 South Quebec Street
Denver, CO 80231
Tel. [phone]
Fluke S.E. Technical Center
Jesse Morse, Service Manager
P.O. Box 6578
940 Nortfi Fern Creek Avenue
Orlando, FL 32803
Tel. [phone]
TWX: 810-850-0185
Fluke Midwestern Tech Center
Bruce Hunt, Service Manager
1287 North Rand Road
Des Plaines, iL60016
Tel. [phone]
TWX; 910-233-4978
Fluke Mideastern Tech Center
John Hines, Service Manager
11501 Huff Court
Kensington, MD 20795
Tel. [phone]
TWX; 710-825-9645
Fluke N.E. Technical Center
Dick Zemba, Service Manager
109 Massachussetts Ave.
Lexington, MA 02173
Tel. [phone]
TWX; 710-826-17 15
Fluke Midwestern Tech Center
Robert Wayne, Service Mgr.
10800 Lyndale Avenue South
Minneapoiis, MN 55420
Tei. 612-8844541
TWX: 910-576-3141
Fluke Eastern Technical Center
Bernard Ciongoii, Service Mgr.
101 Berkshire Ave.
Paterson, NJ 07502
Tei. 201-742-3215
TWX: 710-988-5945
Fluke Eastern Technical Center
Frank Forte, Service Manager
4515 Culver Road
Rochester, NY 14622
Tel -716-342-6940
TWX; 510-253-6145
Fluke S.E. Technical Center
Dwain Cox, Sewice Manager
P.O.Box 9619
1310 Beaman Place
Greensboro, NC 27408
Tel. [phone]
IWX: 510-925-1 173
John Fluke Mfg. Co., Inc.
Bill Fetrow, Tech, Services Spvr.
7001 -220th S.W.
Mountlake Terrace, WA 98043
Tel. [phone]
TWX; 910449-2850
Fluke Canadian Techtiical Center
Tony Unser, Service Manager
640 nth Ave. S.W.
Calgary, Alberta
Tel. [phone]
TWX: 610-821-2233
Fluke Canadian Technical Center
Herb Duval, Service Manager
6427 Northam Drive
Mississauga, Ontario
Tel. [phone]
TWX: 610492-2119
Rev. 5/75

ADDENDUM
Model 893A/AC
Electronic Voltmeter
T.O. 33A1 -12-989-4
'Diis Instruction Manual for the Model 893A AC/DC Differential Voltmeter has been
modified to meet the requirements of Air Force Contract No. F41608-74-D-1756.
All information contained in this manual, modified as required, is applicable to instru-
ments provided on this contract.

JOHN FLUKE MFG.COJNC.
RO, Box 43210
Mountiake Terrace,Washington 98043
Rev. 18/30/71 Rev. 29/22/71 Rev. 36/16/72 Rev. 47/23/73
Rev. 52/10/75
294272
MAY, 1969

The JOHN FLUKE MFG. CO., INC.* warrants each instrument manufactured by them to be free from defects in material and workmanship.
Their obligation under this Warranty is limited to servicing or adjusting an instrument returned to the factory for that purpose, and to making
good at the factory any part or parts thereof; except tubes, fuses, choppers and batteries, which shall, within one year after making delivery to
the original purchaser, be returned by the original purchaser with transportation charges prepaid, and which upon their examination shall dis-
close to their satisfaction to have been thus defective, if the fault has been caused by misuse or abnormal conditions of operations, repairs wifi
be billed at anominal cost. In this case, an estimate wit! be submitted before work is started, if requested.
If any fault develops, the following steps should be taken:
1. Notify the John Fluke Mfg. Co., Inc.,* giving full details of the difficulty, and include the Model number, type number, and serial
number. On receipt of this information, service data or shipping instructions will be forwarded to you.
2. On receipt of the shipping instructions, forward the instrument prepaid, and repairs will be made at the factory. If requested, an
estimate will be made before the work begins, provided the instrument is not covered by the Warranty.
"The foregoing warranty is in lieu of all other warranties, express or implied, including but not limited
to, any implied warranty of merchantability, fitness or adequacy for any particular purpose or use.
Fluke shall not be liable for any special, incident or consequential damages."
SHIPPING
All shipments of John Fluke Mfg. Co., Inc.* instruments should be made via United Parcel Service or "Best Way"** prepaid. The instrument
should be shipped in the original packing carton; or if it is not available, use any suitable container that is rigid. If asubstitute container is used,
the instrument should be wrapped in paper and surrounded with at least four inches of excelsior or similar shock-absorbing material.
CLAIM FOR DAMAGE IN SHIPMENT
The instrument should be thoroughly inspected immediately upon receipt. All material in the container should be checked against the enclosed
packing list. The manufacturer will not be responsible for shortages against the packing sheet unless notified immediately. If the instrument
fails to operate properly, or is damaged in any way. aclaim should ba filed with the carrier. Afull report of the damage should be obtained
by the claim agent, and this report should be forwarded to John Fluke Mfg. Co., Inc.' Upon receipt of this report, you will be advised of the
disposition of the equipment for repair or replacement, include the model number, type number, and serial number when referring to this
instrument for any reason.
The John Fluke Mfg. Co., Inc.* will be happy to answer all application questions which will enhance your use of this instrument. Please ad-
dress your requests to: JOHN FLUKE MFG. CO.. INC,, P, O. Box 7428, SEATTLE. WASHINGTON 98133*.
*For European customers: FLUKE (Nederland) B.V.
Ledeboerstraat 27
Tilburg, Netherlands
**For European customers, Air Freight prepaid.
Fluke Western Technical Center
Mike Nagy. Service Manager
2020 North Lincoln St.
Burbank, CA 91504
Tel. [phone]!
TWX: 910-497-2086
Fluke Western Technical Center
Tom Marshall, Service Manager
4805 Mercury St.
San Diego, CA 9211 1
Tel. [phone]
TWX: 910-337-1273
Fluke Western Technical Center
Attn; Tom Marshall
2359 De La Cruz Bivd
Santa Clara, CA 95050
Tel. [phone]
TWX; 910-338-0121
Fluke S.W. Technical Center
Mel Suelzle, Service Manager
Unit 4
1980 South Quebec Street
Denver, CO 80231
Tel-303-750-1228
Fluke S.E. Technical Center
Jesse Morse, Service Manager
P.O.Box 6578
940 North Fern Creek Avenue
Orlando, FL 32803
Tel. [phone]
TWX: 810-850-0185
Fluke Midwestern Tech Center
Bruce Hunt, Service Manager
1287 North Rand Road
Des Plaines, !L 60016
Tel -312-298-7470
TWX: 9I0-233-497S
Fluke Mideastern Tech Center
John Hines, Service Manager
11501 Huff Court
Kensington, MD 20795
Tel. [phone]
TWX: 710-825-9645
Fluke N.E. Technical Center
Dick Zemba, Service Manager
109 Massachussetts Ave.
Lexington, MA 02173
Tel. [phone]
TWX: 710-826-1715
Fluke Midwestern Tech Center
Robert Wayne, Service Mgr.
10800 Lyndale Avenue South
Minneapolis, MN 55420
Tel. [phone]
TWX: 910-576-3141
Fluke Eastern Technical Center
Bernard Ciongoli, Service Mgr.
101 Berkshire Ave.
Paterson, NJ 07502
Tei. 201-742-3215
TWX; 710-988-5945
Fluke Eastern Technical Center
Frank Forte, Service Manager
4515 Culver Road
Rochester, NY 14622
Tei. 716-342-6940
TWX: 510-253-6145
Fluke S.E. Technical Center
Dwain Cox, Service Manager
P.O.Box 9619
1310 Beaman Place
Greensboro, NC 27408
Tel. [phone]
TWX: 510-925-1 173
John Fluke Mfg. Co.. Inc.
Bill Fetrow, Tech, Services Spvr.
7001 -220th S.W.
Mountiake Terrace, WA 98043
Tel. [phone]
TWX; 910-449-2850
Fluke Canadian Technical Center
Tony Unser, Service Manager
640 11th Ave. S.W.
Calgary, Alberta
Tel. [phone]
TWX; 610-821-2233
Fluke Canadian Technical Center
Herb Duvat, Service Manager
6427 Northam Drive
Mississauga, Ontario
Tel. [phone]
TWX: 610492-21 19
Rev. 5/75

Section Title Page
IINTRODUCTION AND SPECIFICATIONS 1-1
1-1. Introduction 1-1
1-5. Electrical Specifications 1-1
1-6. Differential Voltmeter 1-1
1-
7. Conventional Voltmeter (TVM) 1-2
1-8. General Specifications 1-2
1-9, Environmental Specifications 1-2
1-
10. Mechanical Specifications 1-3
nOPERATING INSTRUCTIONS 2-1
2-
1. introduction 2-1
2-4. Operating Features 2-1
2-6. C^eration from 115/230 volt AC Power Lines 2-1
2-9. Preliminary Operating Procedures 2-1
2-11. C^erational Test 2-1
2-15, Operating Notes 2-4
2-
16. Ground Loop Currents 2-4
2-18. Common Mode Voltages 2-4
2-20. Use of Shorting Link 2-4
2-22. DC Differential Off-Null iiput Resistance ...2-4
2-24. TVM Mode Operation 2-5
2-26. Differential Mode Operation 2-5
2-28. Optional Recorder Output Operation 2-6
2-
30. Applications
2-31. Introduction 2-6
2-33. Measurement of Voltage Excursions About
aNominal Value 2-6
2-35. Measurement of Extremely High Resistances .2-6
2-37. Operation as aNull Detector 2-7
2-
39. Measurement of DBM 2-7
mTHEORY OF OPERATION 3-1
3-
1. fiitroduction 3-1
3-3. Block Diagram Analysis 3-1
3-
4. fiitroduction 3-1
3-6. Conventional TVM Mode 3-1
3-9. Differential Null Mode 3-1
3-12. Optional Recorder Output 3-2
3-14. Circuit Analysis 3-2
3-15. Introduction 3-2
3-17. Power Supply/Battery Charger 3-2
3-20. The Reference Supply 3-3
3-28. Kelvin- Varley Divider 3-4
3-33. AC Converter 3-5
3-38. NullDetector 3-6
3-43. DC Input Divider 3-7
3-46. Optional Recorder Output 3-7
(Continued pg. ii)
89.“^ A

(Table of Contents, continued)
Section Title Page
IV MAmTENANCE 4_1
4-1. Introduction 4_1
4-5. Service Morination 4_i
4-8. Disassembly Eistructions 4-2
4-9. The Model 893A Disassembly Instructions . . 4-2
4-11. The Model 893AR Disassembly Instructions ..4-3
4-13. General Maintenance 4_3
4-14. Periodic Cleaning 4-3
4-17, Fuse Replacement 4-3
4-19. Battery Replacement 4-3
4-21. Precalibration and Troubieshootii^ 4-7
4-22. Introduction 4-7
4-25. Reference Amplifier/Reference Inverter
Checks 4-7
4-28. Null Detector/Divider Checks 4-9
4-31. Kelvin- Varley Divider Checks 4-10
4-34. Recorder Output Option Checks 4-10
4-37. AC Converter Checks 4-11
4-
40. Calibration Procedures 4-12
4-41. Introduction 4-12
4-45. Meter Mechanical Zero Adjust 4-12
4-47. Zener Reference Supply Calibration 4-14
4-49. Null Detector Calibration 4-14
4-51. Kelvin- Varley Divider Calibration 4-15
4-53. DC Voltage Range Calibration 4-15
4-55. AC Converter Calibration .4-16
VLIST OF REPLACEABLE PARTS 5-1
5-
1, Eitroduction 5-1
5-4. Column Description 5-1
5-5. How to Obtain Parts 5-2
5-8. List of Abbreviations 5-2
5-9. Serial Number Effectivity 5-37
APPENDIX A
JOHN FLUKE MFG. CO. WARRANTY
LIST OF SALES REPRESENTATIVES
LIST OF FACTORY AUTHORIZED SERVICE CENTERS
SCHEMATIC DIAGRAM
Rev. 47/23/73 ii
893A

Ut7iiA.
IONS
Figure Title Page
Frontispiece Models 893A and 893AR AC-DC Differential Voltmeter vi
1-1. Model 893A Outline Drawing. 1-3
1-
2. Model 893AR Outline Drawing 1-3
2-
1. The Model 893A Controls, Terminals, and Indicators {Sheet 1of 2). . . 2-2
2-1. The Model 893A Controls, Terminals, and Indicators (Sheet 2 of 2). ..2-3
2-2. The Model 893AR Controls, Terminals, and Indicators (Sheet 1of 2) . . 2-3
2-2. The Model 893AR Controls, Terminals, and Indicators (Sheet 2of 2) . . 2-4
2-3. Readout Dials Versus Null Sens Checks 2-4
2-4. Off-Null DC Input Resistances 2-5
2-5. Bridge Detector-Floating Supply 2-7
2-6. Bridge Detector-Floating Null Detector 2-7
2-
7. 1Volt Range DBM Conversion Table 2-7
3-
1. Model 893A/AR Block Diagram 3-2
3-2. Reference Amplifier/Reference Inverter -Simplified 3-3
3-3. AC Converter Block Diagram 3-5
3-
4. Null Detector Block Diagram 3-6
4-
1. Required Test Equipment 4-2
4-2. Adjustment and Test Point Locations (Sheet 1of 4) 4-4
4-2. Adjustment and Test Point Locations (Sheet 2of 4) 4-5
4-2. Adjustment and Test Point Locations (Sheet 3of 4) 4-6
4-2. Adjustment and Test Point Locations (Sheet 4of 4). .4-7
4-3. Reference Amplifier/Reference Inverter Checks -
Equipment Connections 4-8
4-4. Reference Amplifier/Reference Eiverter Waveforms 4-9
(Continued pg. iv)
iii
aao A

(List of aiustrations, continued)
r-v
ii
Figure Title Page
4-5. Input DC Voltage Versus Range -Checks 4-10
4-6. Null Detector Waveforms 4-10
4-7. Input Voltages Versus Readout Settings -Checks 4-10
4-8. Recorder Output Waveforms 4-11
4-9. AC Converter Range Checks 4-12
4-10. AC Converter Waveforms 4-12
4-11. Summary of Calibration Adjustments (Sheet 1of 2) 4-13
4-11. Summary of Calibration Adjustments (Sheet 2 of 2) 4-14
4-12. TVM Range Checks 4-15
4-13. Jumper Wire Location 4-15
4-14. Jumper Wire Selection 4-16
4-15. Vernier Dial Set Screw Location 4-16
4-16. 100 Volt Range Checks 4-17
4-17. 10 Volt Range Checks 4-17
4-18. 1Volt Range Checks 4-17
4-19. 1Volt Range (0, 1Scale) Checks 4-17
4-
20. 1Volt Range (0. 001 Scale) Checks 4-17
5-
1. 893A AC/DC Differential Voltmeter (Sheet 1of 2) 5-4
5-1. 893A AC/DC Differential Voltmeter (Sheet 2of 2) 5-5
5-2. Front Panel Assembly (893A) 5-6
5-3. Reference Amplifier P/C Assembly 5-8
5-4. Reference Inverter P/C Assembly 5-12
5-5. Null Detector P/C Assembly 5-14
(Continued pg. v)
iv
893A

(List of Illustrations, contiiiued)
Figure Title Page
5-6. Kelviii-Varley P/C Assembly 5-18
5-7. AC Converter P/C Assembly 5-25
5-8. Rear Panel Assembly (893A) 5-26
5-9. 893AR AC/DC Differential Voltmeter (Sheet 1of 2) 5-28
5-9. 893AR AC/DC Differential Voltmeter (Sheet 2of 2) 5-29
5-10. Front Panel Assembly (893AR) 5-30
5-11. Rear Panel Assembly (893AR) 5-31
5-12. Battery and Recorder Output Options 5-33
5-13, Battei'y Option (-01) Installation (Sheet 1of 2) 5-35
5-13. Battery Option (-01) Installation (Sheet 1of ?) 5-35
V
893A

893A

1-1. INTRODUCTION
1-2. The Fluke Model 893A and AR AC-DC Differ-
ential Voltmeters provide conventional or differential
measurements of ac voltages from one millivolt to 1100
volts ac and dc voltages from 10 microvolts to 1100 volts
dc. Conventional (TVM) measurements are made with
an accuracy of ±3% of the selected range to initially
determine the magnitude of the measured voltage. The
differential (NULL) mode is then used with an improved
accuracy of up to 250% over that of the conventional
mode to determine the exact value of the measured volt-
age. One linear meter-scale greatly simplifies all
measurements made with the instrument. Whenever the
instrument is operated on the differential mode, an in-
line digital readout representing the magnitude of the
measured voltage is available from the front panel Read-
out dials.
1-3. Two versions of the instrument are available and
are identified as the Model 893A or Model 893AR. The
Model 893A is aportable unit, half-rack in width, with
atilt-down carrying handle. This handle detents into
the instrument's feet to serve as atilt-bale during
bench-top use of the instrument. The Model 893AR is
also aportable unit, but is of proper width for instal-
lation in astandard electronic equipment rack. Car-
rying of this instrument is provided by two front panel
handles, Atilt-down bale located on the bottom of the
instrument facilitates bench-top use of the instrument,
1-4. Arechargeable battery and recorder output op-
tions are also available for either version of the instru-
ment. These options can be installed at the factory,
upon request, or in the field. Option Kit 893A-7001
comprises the rechargeable battery pack and, when in-
stalled in the instrument, is identified as the -01 option
on the rear panel decal. Option Kit 893A-7002 com-
prises the recorder output and, when, installed in the
instrument, is identified as the -02 option on the rear
panel decal.
1-5. ELECTRICAL SPECIFICATIONS
1-6. DIFFERENTIAL VOLTMETER
DC ACCURACY ,£3 'z- y
±{0. 01% of input +0. 001% of range +10 uv) from 0 to 1100
volts dc at 23®C ±2“C with up to 80% relative humidity.
±(0. 02% of input +0. 001% of range +10 uv) from 0to 1100
volts dc at 10“C to 40“C (50*F to 104“F) with up to 70%
relative humidity.
AC ACCURACY O>tf-
At 23°C ±2'’C with less than 70% relative humidity:
50 Hz to lO kHz
0. 001 to 500 volts ac ±(0. 05% of input +25 uv)
500 to 1100 volts ac ±0. 1% of input
At 10°C to 40°C with less than
5Hz to 10 Hz
0. 001 to 1100 volts ac
10 Hz to 20 Hz
0. 001 to 1100 volts ac
20 Hz to 50 Hz
0. 001 to 1100 volts ac
50 Hz to 20 kHz
0. 001 to 110 volts ac
110 to 1100 volts ac
20 kHz to 50 kHz
0.001 to 110 volts
70% relative humidity:
±{l% of input +250 uv)
±(0. 5% of input +100 uv)
±(0. 15% of input +25 uv)
±{0. 1% of input +25 uv)
±0. 15% of input
±(0. 15% of input +25 uv)
1-1
89,3A

50 kHz to 100 kHz
0. 1to 110 volts ac ±0. 5% of input
1-8. GENERAL SPECIFICATIONS
INPUT AND NULL VOLTAGE RANGES ELECTRICAL SPECIFICATIONS Completely solid-state
INPUT RANGES
1
10
100
1000
DC NULL RANGES
0.001 ,0.01 ,0.1
0.001 ,0.01 ,0.1,1.0
0.01 ,0.1,1.0,10
0.1,1.0,10 ,100
INPUT RANGES
1
10
100
1000
AC NULL RANGES
0.001, 0. 01^ 0.
1
0.01, 0.1, 1.0
0. i, 1.0, 10
1.0, 10, 100
DC INPUT RESISTANCE
Infinite at null from 0to 1100 volts dc.
AC INPUT IMPEDANCE
One megohm shunted by less than 20 pf on all ranges.
OVERRANGE
10% overrange capability on each range.
METER RESOLUTION
10 microvolts maximum resolution.
1ppm of range for dc ranges above one volt.
10 ppm on the one volt dc range and all ac ranges.
READOUT DIAL RESOLUTION
10 microvolts maximum (10 ppm of range).
1-7. CONVENTIONAL VOLTMETER (TVM)
DC VOLTMETER ACCURACY
±3% of range.
INPUT RESISTANCE OF NULL DETECTOR
10 megohms on the 0. 01 and 0, 001 volt ranges and 100
megohms on all other ranges.
REFERENCE ELEMENT
Temperature compensated zener diodes.
REGULATION OF REFERENCE SUPPLY
0. 0005% for a10% line change.
REFERENCE VOLTAGE STABILITY (Peak-to-Peak)
10 ppm per hour
20 ppm per day
40 ppm per month
90 ppm per year
KELVIN-VARLEY DIVIDER ACCURACY
±0. 005% of readout dial setting above l/lO of full-scale.
RECORDER OUTPUT
Available as the -02 option, adjustable from 0to ±0.2
volts for an end-scale meter deflection. Low side
grounded and loading does not effect deflection accuracy.
POLARITY
Reversible with front panel control.
WARM-UP TIME
Less than one minute.
DC COMMON MODE REJECTION
120 db (1 uv/volt of common mode voltage) for maximum
of ±500 volts.
AC VOLTMETER ACCURACY
5Hz to 20 kHz
O.OOl to 1100 volts ac ±3% of input
20 kHz to 100 kHz
0, 001 to 110 volt ac ±3% of input
DC INPUT RESISTANCE
RANGE INPUT RESISTANCE -Megohms
1000 100
100 100
10 100
1100
0.1-0-0.
1
100
*0.01 -0-0.01 10
*0.001 -0-0.001 10
These ranges obtained using null ranges with Readout
dials set to zero.
AC INPUT IMPEDANCE
One megohm shunted by less than 20 pf on all ranges.
OVERRANGE
10% overrange capability on each range.
1-2
AC COMMON MODE REJECTION
Up to 100 volt peak-to-peak, 50 to 500 Hz signal, pro-
duces no measurable instrument error for dc measure-
ments.
INPUT POWER
115/230 volts ac, 50 to 500 Hz, at approximately four
watts for line operation and approximately eight watts
when recharging batteries on the -01 option equipped
instruments. Minimum of eight hours operation on fully
charged batteries of the -01 option equipped instru-
ments.
1-9. ENVIRONMENTAL SPECIFICATIONS
OPERATING TEMPERATURE RANGE
Within dc accuracy specifications from 10° Cto 40° C
(50°F to 104°F), derated at 15 ppm/°C outside these
limits to 0°C and 50°C (32°F and 122°F).
Within ac accuracy specifications from 10° Cto 40° C
(50°F to 104° F), derated at 40 ppm/°C outside these
limits to 0°C and 50°C (32°F and 122°F).
HUMIDITY
Within all specifications up to 80% relative humidity be-
low 25° C.
6/16/72
893A

Within all specifications up to 70% relative humidity a-
bove 25°C.
STORAGE TEMPERATURE RANGE
Model 893A/AR -40°C to 70°C {-40°F to 158°F)
Model 893A/AR-01 -40' Cto 60° C(-40° Fto 140° F}
SHOCK AND VIBRATION
Meets MIL-T-945A.
1-10. MECHANICAL SPECIFICATIONS
SIZE
Model 893A
See Figure 1-1
Model 893AR
See Figure 1-2
WEIGHT
Model 893A
Approximately 12 pounds
Model 893AR
Approximately 12 pounds
Option -01 (Option kit 893A-7001)
Approximately 2pounds
Option -02 (Option kit 893-7002)
Approximately 0. 3pounds
OPTION KIT 893A-7001
Provides rechargeable battery pack for installation in
either version instrument.
OPTION KIT 893A-7002
Provides arecorder output for installation in either ver-
sion instrument.
8-30-71
1-3
893A

2-1. INTRODUCTION
2-2. This section of the manual contains information
necessary for you to effectively operate your Model 893
AC/DC Differential Voltmeter. It is recommended that
you thoroughly read and understand this section of the
manual before attempting to operate your instrument.
POWER
RANGE
NULLS SENS
MODE
Readout dials
ON/LINE OPR
1000
TVM
+
000 .^
2-3. Should any difficulties be encountered during
the operation of your instrument, please feel free to
contact your nearest John Flulce Sales Representative
or write directly to the John Fluke Mfg. Co. ,Inc.
,
P.O. Box 43210, Mountlake Terrace, Wn. 98043, with a
statement of your problem. Acomplete list of Sales
Representatives is contained at the rear of tMs manual.
2-4. OPERATING FEATURES
2-5. All of the controls, terminals, and indicators
for the Model 893A and the Model 893AR are illustrated
and described in Figure 2-1 and Figure 2-2,
2-6. OPERATION FROM 115/230 VOLT
AC POWER LINES
2-7. The Model 893 may be operated from either a
115 or 230 volt ac power line. The input power trans-
former primary is composed of two windings which,
when connected in parallel, allows the instrument to be
operated from a115 volt ac power line or, when the
windings are connected in series, allows the instru-
ment to be operated from a230 volt ac power line.
2-8. Arear panel 115/230 slide switch (S5) provides
the necessary power transformer primary winding con-
nections when placed to the desired 115 or 230 volt
position.
2-9. PRELIMINARY OPERATING PROCEDURES
2-10. Connect the Model 893 power cord to available
line power. If your instrument does not contain the
-01 option, perform only step a. If your instrument
contains the -01 option, perform steps athrough c.
WARNING!
The instrument case is connected to the
round pin of the three-prong connector
located on the power cord. Whenever the
instrument is operated from ac line power,
ensure that this round pin is connected to
ahigh quality earth ground.
a. Place the instrument controls as follows and allow
at least one minute of circuit stabilization before
attempting any measurements.
2/10/75
The Readout dial labeled OO in the preceding
step, represents the extreme right-hand
vernier dial.
b. Place the -01 option equipped instrument POWER
switch to BAT CHK, observing that the meter needle
deflects to the left of the -, 2volt increment. If
the batteries are adequately charged, the instru-
ment can be operated on battery power by placing
the POWER switch to either BAT OPR or BAT
OPR/LINE ISOL. To completely isolate your in-
strument from the line power ground, disconnect
the power cord from line power.
c. If the BAT CHK test results in adeflection of less
than .2volts on the meter, place the POWER switch
to BAT CHG and operate the instrument from line
power until the batteries are adequately charged.
All measuremaits can be performed during recharg-
ing of the batteries. Should the batteries fail the
BAT CHK test after 16 hours of recharging, replace-
ment of the batteries may be necessary. Refer to
Section IV, paragraph 4-19 and 4-20 for battery re-
placement instructions.
Battery manufacturers recommend that nickel-
cadmium batteries should not be stored for
extended periods of time without recharging
at least every 90 days. Storage temperatures
below 25‘^C are recommended.
2-11. OPERATIONAL TEST
2-12. The following information is provided for the
operator to initially verify instrument operation. These
tests will only check relative instrument operation and
are not intended as instrument performance checks.
Should you wish to check the accuracy of the instru-
ment against the specifications contained in Section I,
refer to the Performance Checks contained in Section
rv of this manual.
2-13. To determine relative instrument operation,
perform the operations described in the Preliminary
Operating Procedures (paragraphs 2-9 and 2-10) and
proceed as follows:
a. Place the RANGE control to 1.
2-1
A

XD
©METER Indicates the magnitude and poiarlt/ of the measured voltage on the TVM mode. On
the differential mode, the meter or -deflection Indicates that the measured voltage is
above or below the readout dial indication.
©POWER SWITCH Controls application of input power to the instrument. When placed to the LINE OPR
position, the instrument is operated from the available line power. On Instruments
equipped with the 01 Option, additional switch positions of BAT CHK, BAT OPR-LINE
ISOL, and LINE OPR-BAT CHG are Included, When placed to the BAT CHK position ,
the front pane! meter indicates the charge condition of the battery pack, Ameter
indication of at least -.2 is required before the instrument is to be operated from the
battery power. When placed to the BAT OPR-LINE ISOL position, the Insrument is
operated from battery power and the power transformer is completely disconnected from
line power. However, to completely isolate the instniment circuitry from power line
ground, the line power cord must be disconnected. When placed to the LINE OPR-BAT
CHG position, the instrument Is operated from line power and the battery pack Is being
charged
.
©NULL SENS SWITCH Provides selection of the TVM mode of operation and selection of the various full- scale
null detector sensitivity ranges when the instrument is operated on the differential mode.
©RANGE SWITCH Allows selection of the desired input voltage range of the instrument, while at the same
time simultaneously positioning the readout dial decimal point and selecting the avail-
able ranges of the NULL SENS switch.
©READOUT DIALS Provide an in-line digital readout of the measured voltage when the instrument is
operated on the differential mode.
©MODE SWITCH Selects the AC or DC mode of operation. This switch should be ploced to the +position
on the DC TVM mode. The ±positions provide ameans of reversing the internal refer-
ence supply voltage on the dc differential mode.
2-2
Figure 2-1. THE MODEL 893A CONTROLS, TERMINALS, AND INDICATORS (Sheet 1of 2)
893A