Fluke 8505A User manual

Instruction Manual
P/N 638841
MARCH 1983 REV 1,3/86
®1986, John Fluke Mfg. Co., Inc. All Rights Reserved. Litho in U.S.A.

1-1. INTRODUCTION
1-2. This eight-section manual provides comprehensive
information for installing, operating and maintaining
your Fluke digital multimeter. Complete descriptions and
instructions are included for the instrument mainframe,
for all modules necessary in making dc volts
measurements, and for any optional modules ordered
with the instrument. Appropriate sectionalized
information is also included with any optional modules
subsequently ordered and may be inserted in Section 6.
1-3. DESCRIPTION
1-4. The multimeter features 6-1/2 digit resolution, full
annunciation and simplicity of operation. Modular
construction, microprocessor control, and abus structure
provide excellent flexibility. Memory programming from
the front panel (or through aremote interface) controls all
measurement parameters, mathematic operations and
special operations. An averaging mode is available to
automatically optimize display resolution and stability
for each function and range. The standard hardware
configuration allows for measurement of dc volts in five
ranges with 100 nV resolution on the lowest range.
Optional modules are available for ac volts (four ranges),
ac or dc current (five ranges), and resistance (eight ranges)
in two-wire or four-wire arrangements.
1-5. Modular Construction
1-6. Considerable versatility is realized through unique
contruction. All active components are contained in
modules which plug into amainframe motherboard. This
module-motherboard mating, combined with bus
architecture and microprocessor control, yields both ease
of option selection and reduced downtime.
NOTE
The A3 Isolator PCS is standard in the
8505A. This assembly is documented in
Section 6ofthis manual as Option -08A.
1-7. Microprocessor Control
1-8. All modules function under direct control of a
microprocessor based controller. Each module is
addressed by the controller as virtual memory. External
reference values and offsets can be applied separately,
stored in memory, and automatically used as factors in all
subsequent readings. Digital filtering utilizes averaged
samples for each reading.
1-9. Software Calibration
1-10. The 8505A features microprocessor-controlled
calibration of all ranges and functions. Any range can be
calibrated using areference input of any known value
from 60% of range to full scale. Software calibration can
be performed using front-panel or remote control,
allowing recertification without opening the case or
removing the multimeter from the system.
1-11. R@elreufating Remainder A/D Conversion
1-12. The multimeter adapts Fluke’s patented
recirculating remainder (R2)A/D conversion technique
to microprocessor control. This combination provides
fast, accurate, linear measurements and long-term
stability.
1-13. Options and Accessories
1-14. Remote interfaces, ac converters, acurrent
converter, and an ohms converter are among the
numerous options and accessories available for use with
the multimeter. Refer to Tables 1-1 and 1-2 for complete
listings. AC conversion can be accomplished with either
the AC Averaging module (Option 01) or the RMS
module (Option 09A). Any one of the three Remote
Interface modules (Option 05, 06, or 07) can be installed
at one time.
1-15. SPECIFICATIONS
1-16. Mainframe specifications with dc volts and dc
ratio measurement capability are presented in Table 1-3.
Optional function specifications are supplied with the
respective option modules and included in Section 6.

8505A
Table 1-1. Options
OPTION
NO. NAME NOTES
01 AC/DC Converter (Averaging) 1, 3
02A Ohms Converter
03 Current Shunts 3
05 IEEE Standard 488-1975 Interface 2
06 Bit Serial Asynchronous Interface 2
07 Parallel Interface 2
09A AC/DC Converter (True RMS) 1, 3
1) Options 01 and 09A cannot be
installed simultaneously.
2) Only one of Options 05. 06. and 07
can be installed at any time.
3) For the ac portion of Option 03 to
operate, either Option 01 or 09A .....
must be installed.
Table 1-2. Accessories
MODEL OR
PART NO. NAME
M04-205-600 574-inch Rack Adapter
M00-260-610 18-inch Rack Slides
M00-280-61
0
24-inch Rack Slides
80K-6 High Voltage Probe
80K-40 High Voltage Probe
83RF High Frequency Probe
85RF High Frequency Probe
Y8001 IEEE Std. Cable, 1Meter Length
Y8002 IEEE Std. Cable, 2Meter Length
Y8003 IEEE Std. Cable, 4Meter Length
MIS-701 IK* Extender Card
MIS-71 90K’ Static Controller
MIS-7191K* Test Module
MIS-7013K* Bus Interconnect and Monitor
Tor use during service or repair.
j
Table 1-3. Specifications
GENERAL SPECIFICATIONS
Dimensions 10.8 cm High x43.2 cm Wide x42.5 cm Long
(4.25 in High x17 in Wide x16.75 in Long) (See Figure 1-1)
Weight
BASIC ... .10 kg (22 lbs)
FULLY LOADED .... 12 kg (26 lbs)
Operating Power
VOLTAGE .... 100V ac, 120V ac, 220V ac, or 240V ac (±10%)
BASIC INSTRUMENT POWER . .
.
—12 watts
FULLY LOADED POWER 24 watts
FREQUENCY —47 Hz to 63 Hz (400 Hz available on request)
Warm-Up —2hours to rate accuracy
Shock and Vibration —Meets requirements of MIL-T-28800 for type III, class 5,
style Eequipment.
Temperature Range
OPERATING .... 0°C to 50°
C
NON-OPERATING .... -40° Cto 70°
C
Humidity Range
0°C TO 18°C ....80% RH
18°C TO 40° C. . . . 75% RH
40° CTO 50° C... . 45% RH
Maximum Terminal Voltage
LO TO GUARD 127V rms
GUARD TO CHASSIS 500V rms
HI SENSE TO HI SOURCE .... 127V rms
LO SENSE TO LO SOURCE .... 127V rms
HI SENSE TO LO SENSE .... 1000V rms or 1200V dc
HI SOURCE TO LO SOURCE .... 280V rms
1-2

8505A
DC VOLTAGE
Input Characteristics
FULL SCALE RESOLUTION INPUT
RESISTANCE
RANGE 6’/
2DIGITS rvh 1
DIGITS*
6’/2
DIGITS
100 mV 200.0000 mV —100 nV >10,000MQ
IV 2.000000V —1//V >10,000MQ
10V 20.00000V 1/iV 10 >10,000MQ
100V 128.0000V —100 //V 10MQ
1000V 1200.000V —1mV 10MQ
’7'/
2-digit resolution: In AVG operating mode.
Accuracy
DC VOLTS: ±(% of Reading +Number of Counts)
24-HOUR 90-DAY
RANGE 23°C ±1°C’ 23° C±5°C
OPERATING MODE OPERATING MODE
NORM AVG NORM AVG3
100 mV 0.0018 +15 0.0010 +80.0025 +40 0.0020 +8
IV 0.0008 +70.0005 +40.0015 +80.0012 +6
10V 0.0006 or 6* 0.0005 or 502*0.0010 +80.0008 +602
100V0.0010 +60.0005 +50.0018 +80.0015 +6
1000V 0.0008 +6 0.0005 +50.0018 +80.0015 +6
'Whichever is greater
>90-Day: 23° C±5°C
Add to the 90-day specification per month the following %of Reading and Number of Counts.
RANGE OPERATING MODE
NORM AVG3
100 mV
IV
10V
100V
1000V
0.00017 +5.6
0.0001 +0.1
0.0001 +0.1
0.00013 +0.1
0.00013 +0.1
0.0001 +0.1
0.0001 +0.1
0.00008 +I2
0.0001 +0.1
0.0001 +0.1
NOTES:
’Relative to calibration standards, 4-hour warm-up, within 1hour of dc zero. After software calibration
add the following to the 24 hour accuracy specification:
TIME SINCE INTERNAL
(HARDWARE) CALIBRATION NUMBER OF COUNTS'
<30 Days 0
<90 Days 1
<1 Year 2
>1 Year 3
'With 6VS?-digit display. For 714-digits, multiply Number of Counts by 10.
27Vi>-digit mode of operation.
3After 4-hour warm-up, within 1hour of dc zero.
1-3

8505A
Table 1-3. Specifications (cont)
Operating Characteristics
TEMPERATURE COEFFICIENT: ±(% of Reading +Number of Counts)/°C
RANGE 0°C TO 18°C AND 28°C TO 50°C
100 mV 0.0003 +5
IV 0.0003 +1
10V 0.0002 +0.5*
100V 0.0003 +1
1000V 0.0003 +0.5
’Multiply Number of Counts by 10 for AVG operating mode (7Vfe-digit).
INPUT BIAS CURRENT
AT TIME OF ADJUSTMENT 1-YEAR 23° C±1°C TEMPERATURE COEFFICIENT
<±5 pA <±30 pA <±1 pA/°C
ZERO STABILITY Less than 5/iV for 90 days after afour-hour warm-up. Front panel
pushbutton zero is provided for permanent storage of azero
correction for each range. Zero may be turned off at any time.
MAXIMUM INPUT VOLTAGE +1200V dc or 1000V rms ac to 60 Hz, or 1400V peak above 60 Hz may
be applied continuously to any dc range without permanent damage.
Maximum common mode rate of voltage rise is 1000V //vsec.
ANALOG SETTLING TIME
FILTER MODE FILTER
COMMAND TO 0.01% OF
STEP CHANGE TO 0.001% OF STEP CHANGE
Bypassed FI 2ms 20 ms
Fast F0 or F3 40 ms 50 ms
Slow For F2 400 ms 500 ms
DIGITIZING TIME
Line Synchronous For 2° to 217 samples per reading digitizing time is from 4ms to 9
minutes 6seconds using a60 Hz ac line with times increasing 20%
using a50 Hz ac line. Selectable in 18 binary steps.
Line Asynchronous 2ms. {In 3byte binary mode with dc zero, offset, limits and calibration
factors turned off.)
NOISE REJECTION
Normal Mode Rejection
LINE
FREQUENCY FILTER
MODE 4SAMPLES/ READING 32 SAMPLES/ READING 128 SAMPLES/
READING
50 hertz Fast 60 dB 70 dB 75 dB
50 hertz Slow 85 dB 90 dB 95 dB
60 hertz Fast 60 dB 70 dB 75 dB
60 hertz Slow 90 dB 95 dB 100 dB
Common Mode Rejection 160 dB at 60 hertz with 1kO in series with either lead, and 4samples or
more per reading. Greater than or equal to 100 dB with less than 4
samples per reading.
1-4

8505A
Table 1-3. Specifications (cont)
DC RATIO
Accuracy
EXTERNAL REFERENCE VOLTAGE’ ACCURACY’
±20V to ±4QV ±(A +B+0.001%)
±Vmin to ±20V ±(A +B+(0.02% /|Vxref D)
'Maximum External Reference Voltage =±40V between External Reference HI and LO terminals,
providing neither terminal is greater than ±20V relative to the Sense LO or Ohms Guard2terminals.
Operating Characteristics
INPUT IMPEDANCE External Reference HI or LO >10,000 MQ relative to Ohms Guard2or
Sense LO.
BIAS CURRENT External Reference HI or LO relative to Ohms Guard2or Sense LO <5
nA.
SOURCE IMPEDANCE Resistive Unbalance (External Reference HI to LO) <4 kfl Total
Resistance to Sense LO from either External Reference HI or LO <20
kQ.
MAXIMUM OVERLOAD VOLTAGE ... ±180V dc or peak ac (relative to Ohms Guard2orSense LO). ±360V dc
or peak ac (External Reference HI to LO).
NOISE REJECTION
INPUT
TERMINALS NORMAL MODE COMMON MODE
Sense Same as dc volts Same as dc volts
External line frequency and line frequency and
Reference 2x line frequency 2x line frequency
>100 dB >75 dB
RESPONSE TIME
Analog Settling Time
FILTER MODE FILTER
COMMAND TO 0.01% OF STEP CHANGE TO 0.001% OF
STEP CHANGE
Bypassed FI 2ms 20 ms
Fast F0 or F3 40 ms 50 ms
Slow F or F2 400 ms 500 ms
NOTES: (DC Ratio)
'A -10V dc range accuracy for the appropriate period of time.
BInput signal function and range accuracy for the appropriate period of time.
Vdiin Minimum allowable External Reference Voltage =±0. 0001V, or V.nput /109(whichever is greater).
lV/r..f| Absolute value of the External Reference Voltage
Ohms Guard is available through the rear input.
1-5

8505A
Table 1-3. Specifications (cont)
DC RATIO (cont)
Operating Characteristics (cont)
Digitizing Time For 2° to 2’ 7samples per reading digitizing time is from 196 ms to9
minutes 6seconds using a60 Hz ac line with times increasing 20%
using a50 Hz ac line. Selectable in 18 binary steps.
MAXIMUM RATIO DISPLAY +1.00000 E±9
EXTERNAL TRIGGER INPUT
Polarity
High Level
Low Level
Pulse Width
Connector
Maximum Input
Maximum Shell to Ground
May be wired internally for either rising or falling edge. Factory wired
for falling edge.
+4.3V (minimum)
+0.7V (maximum)
10 fjs (minimum)
BNC with the outer shell at interface common
±30V
±30V
SCAN ADVANCE OUTPUT
Polarity
High Level
Low Level
Pulse Width
Connector
Maximum Shell to Ground
Positive
>+4V (TTL High)
<+0.7V (TTL Low)
3/js (minimum)
BNC with the outer shell at interface common
±30V
13.25 cm r*
(5.219 in) 5.72 cm
3.77 cm
(1.484 in) FRONT VIEW
(4.25 in)
1.27 cm
(.5 in)
41.66 cm (16.4 in)
-46.23 cm (18.2 in)
RIGHT SIDE VIEW
Figure 1-1. Dimension Drawing
1-6

2-1. INTRODUCTION
2-2. installation and operation of the multimeter are
explained in this section. These instructions should be
read thoroughly prior to multimeter operation. Once a
familiarization with the instrument is achieved, parts of
this section will serve as aquick reference. Explanations
and applications are provided for all standard functions
and operations. Should any difficulties arise, contact
your nearest Fluke Sales Representative (listed in Section
7) or the John Fluke Mfg. Co., Inc.; P.O. Box C9090;
Everett, WA. 98206; tel. [phone]).
2-3. SHIPPING INFORMATION
2-4. The multimeter is packaged and shipped in afoam-
packed container. Upon receipt of the instrument, a
thorough inspection should be made to reveal any
possible shipping damage. Special instructions for
inspection and claims are included with the shipping
container.
2-5. If reshipment is necessary, the original container
should be used. 1fthe original container is not available, a
new container can be obtained from John Fluke Mfg.
Co., Inc. Please reference the instrument model number
when requesting anew shipping container.
2-6. INSTALLATION
2-7. Non-marring feet and atilt-down bail arrangement
are installed on the instrument for field or bench use. A
rack-mounting kit and rack slides are available for use
with the standard 19-inch equipment racks. Information
regarding installation and rack-mounting accessories is
contained in Section 6.
2-8. The multimeter operates from 100, 120, 220, or
240V ac (±10%) at 50 or 60 Hz. Line voltage selection
must be verified before the power cord is connected. This
verification procedure is explained in Section 4.
WARNING
TO AVOID ELECTRICAL SHOCK, PRO-
PERLY GROUND THE CHASSIS. AGROUND
CONNECTION IS PROVIDED ON THE
THREE-PRONG POWER CONNECTOR. IF
PROPER GROUND IN YOUR POWER
SYSTEM IS IN DOUBT, MAKE ASEPARATE
GROUND CONNECTION TO THE REAR
PANEL CHASSIS BINDING POST.
OTHERWISE, THE POSSIBILITY OF
ELECTRICAL SHOCK MAY EXIST IF HIGH
VOLTAGE IS MEASURED WITH THE LEADS
REVERSED (INPUT HI GROUNDED).
2-9. OPERATING FEATURES
2-10. Front and rear panel features are illustrated in
Figure 2-1 and described in Table 2-1. Use this
information for initial familiarization with the
multimeter. Afull explanation of all features is presented
later in this section.
2-11. OPERATING NOTES
2-12. Input Power
2-13. Abinding post on the rear panel has been
provided as an earth ground connection. Line voltage
selection (100, 120, 220, or 240V ac) is explained in
Section 4. With the exception of proportionately slower
reading rates and filter time-outs, operation at 50 Hz is
identical to that at 60 Hz.
2-14. The line fuse (0.5A MDL Slow Blow for 100 or
120V ac, or 0.25 MDL Slow Blow for 220 or 240V ac) is
located on the lower right side of the rear panel (in the
heat sink). The current and ohms protection fuse (1.5
A
AGC) is located in the lower right-hand corner of the
front panel for front input connections and on the left side
of the rear panel (as seen from the rear) for rear input
connections. Refer to Fuse Replacement in Section 4
before replacing any fuse.
2-1

85i
ITEM NAME
Displays 5Vs, QVz or 7Vz digits with polarity and decimal point. Also
displays errors and warnings, prompts, numerics, recalled values, and
limits indications.
Mantissa Field
Exponent Field Polarity and value of exponent shown for engineering notation of
display value. In Averaging or Calibration mode, the exponent may
be used as an extra digit of resolution.
Function Annunciators Annunciator lights to indicate function selection. VDC and VAC
annunciators will both light when respective functions are simul-
taneously selected and the RMS Converter is installed.
TRIGGER Push Buttons TRIGGER push buttons used to select continuous (AUTO) or indiv-
idual (MANUAL/EXTERNAL) measurement triggers.
IT '
IIl: ;
-Vj—
2-2

8505A
Table 2-1. Controls, Indicators, and Connectors (cont)
BDESCRIPTION
5FUNCTION Push Buttons Used to select any of six measurement functions: voltage (V DC, V AC,
or VDC and VAC), current (A DC or AAC), or resistance (OHMS).
6RANGE Push Buttons AUTO toggles into/out of Autoranging mode, changing range only
when necessary. The up/down buttons exit Autoranging and increase/
decrease one range with first use, step up/down one range with each
additional use.
7ZERO Push Button Used to toggle into/out of the Zero mode (V DC or OHMS only). A new
zero value is stored each time the mode is entered. This value is applied
to the selected range and to all higher ranges within the same function.
Also used to recall zero values. Refer to text for use with Calibration
Memory.
8MEMORY Push Buttons STORE is used to initiate memory entry for displayed values or numeric
entries. RECALL commands display of a memory value. HI and LO
are used when storing or recalling limits, or when recalling peak values.
Average Push Button AVG toggles into/out of Averaging mode.
9Input Terminals Measurement connection terminals.
10 Guard Selector GUARD is connected to SENSE LO when disengaged (out); GUARD
is floated to allow external connection when engaged (in).
11 Ohms Selector Push in for 4-wire ohms measurement using OHMS SENSE (HI,
LO) and OHMS SOURCE (HI, LO) terminals. Push again to disengage
for 2-wire ohms measurements using OHMS SENSE (HI, LO)
terminals.
12 Rear Input Selector Push in to connect rear analog input terminals and disconnect front
terminals. Push again to disengage, reconnecting front terminals and
disconnecting rear terminals. Position of the switch can be sensed
remotely.
13 Current/Ohms Fuse Use AGC 1.5A.
14 MODIFIERS Push Buttons SAMPLE and FILTER modify the manner in which areading is taken
(measurement parameters). EXT REF, OFFSET, and SCALING
modify the reading value (mathematic operations). LIMITS and PEAK
modify the usage of the measurement value (special operations).
15 Numeric Entry Push Buttons When enabled by initially pushing the STORE button, these push
buttons can be used to enter numerics, exponents and related polarity
signs.
16 CONTROL Push Buttons RESET initiates apower-up reset.
LCL/RMT usage depends on the remote interface in use:
a. If the IEEE Interface (-05) is used, LCL/RMT toggles from remote
to local, but not from local to remote.
b. If the Bit Serial (-06) or Parallel (-07) Interface is used, LCL/RMT
toggles between local and remote.
2-3

8505A
Table 2-1. Controls, indicators, and Connectors (cont)
ITEM NAME DESCRIPTION
17 Status Annunciators SAMPLE flashes to show anew reading in progress.
FILTER lights whenever slow filter is selected.
AUTO lights for Autoranging.
EXT lights when External Reference is enabled (disables Scaling).
AVG/CAL lights (steady) for Averaging or flashes for Calibration mode.
ZERO lights when aVDC or OHMS zero correction value is in use.
OFFSET lights when Offset mode is enabled.
SCALE lights when Scaling mode is selected (disables Ext Ref).
PEAK lights when Peak mode is enabled.
REMOTE lights when the multimeter is controlled through aremote
interface.
18 POWER Switch Push ON/push OFF. The Calibration switch (item 24) must be off before
cycling power on or off.
19 Scan Advance Output TTL compatible output signals to external scanner (50-ohm output
impedance).
20 Chassis Ground Binding post for ground connections.
21 Remote Interface Access Port Connector on optional remote interface module accessible here.
22 Power Connector Three-prong connector accepting line cord with ground wire.
23 Line Fuse Use ViA Slow Blow for 100 or 120V ac, !4A Slow Blow for 220 or 240V ac.
Refer to Fuse Replacement in Section 4.
24 Calibration Switch Activates Calibration mode (AVG/CAL) annunciator flashes).
25 Externa! Trigger Input Enabled by front panel MANUAL/EXTERNAL push button.
26 Rear Analog Input Connection Alternate connections for ail front panel inputs —enabled when
Rear Input Selector on front panel is pushed in. EXT REF HI and LO
inputs are also included, but are not switched by the Rear Input
Selector.
27 Rear Input Fuse Use AGC 1.5A.
2-15. Required Hardware
2-16. The multimeter must be equipped with the
following modules for standard operation (dc volts).
1. Controller (blank display if not installed)
2. Active Filter (Error 2 if not installed)
3. A/D Converter (Error 5if not installed)
4. Isolator (Error 9at power-up if not installed)
2-17. Additional modules are necessary when using the
multimeter in ac volts, dc current, ac current, or resistance
2-4
functions or for remote control. Separate modules for
averaging ac or rms ac measurements are available: only
one of these modules may be installed at one time. If it is
necessary to check, install or replace modules, refer to
Module Installation and Removal procedures in Section
4.
2-1 8. An “Error 9” indication appears in the multimeter
display whenever an optional function is selected and the
respective function module is faulty or missing. At power-
up, the multimeter identifies all installed options by
displaying “CXXXXXX” (“X” =Option number). An
“8” in the exponent display identifies an installed Isolator.

2-19. Power-Up Configuration
2-20. At power initialization, or whenever the RESET
button is pushed, the multimeter assumes the power-up
configuration. Basically, the instrument assumes the
VDC function with all modes and values disabled. The
power-up configuration is fully defined in Table 2-2.
2-21. Display
2-22. MEASUREMENT READING
2-23. The measurement display consists of mantissa and
exponent fields. The mantissa presents polarity, 5-1/2, 6-
1/2, or 7-1/2 digit resolution (range and function
dependent) and automatic decimal placement. In
addition, the mantissa displays numeric storing entries,
recalled values, error and warning information, and
interactive programming information (prompts).
Decimal point positions are labeled. (1, 10, 100, Ik) to
correspond with range settings (as defined in Figure 2-3).
2-24. When very large or small readings are displayed,
the exponent field is also used to maintain maximum
8505A
resolution. Anegative or positive exponent field polarity
indicates multiplication of the mantissa by the displayed,
power of ten (-3 means .001, +3 means 1000). Exponent
values of -6, -3, +3, or +6 are available for displayed
readings. Additional exponents of -9 and +9 are
available for offset and scaling numeric entries.
2-25. When the Averaging mode is selected, the
exponent may serve as an additional digit of resolution.
When the Limits mode is selected, the entire measurement
display is devoted to an indication of HI, LO, orPASS.
2-26. ANNUNCIATORS
2-27. Any valid function selection causes one of the
function annunciators (V DC, VPCyADC, AAC,
OHMS) to light. The VDC annunciator normally lights
in the power-up or reset configuration. However, if the
DC Signal Conditioner module is faulty or not installed
and afunctional RMS Converter module is installed,
power-up or reset causes the VAC annunciator to light.
Two function annunciators (V DC and VAC) light when
Function
SELECTION OF NEW FUNCTION (1)
CONDITION CONDITION DISPLAY
DC Volts VDC on New Function VDC,VAC,ADC, AAC
or OHMS on
Range 1000V Manual Autoranging AUTO on
Trigger Auto 33I1SS Retains Previous Trigger Mode SAMPLE flashing or off
Filter F0 FILTER off Retains Previous Filter Mode (2) FILTER on or off
Sample 7SAMPLE flashes Retains Previous
Sample Setting (2)
SAMPLE flashes
Offset Off, Value 0Off, retains value OFFSET off
Scaling Off, Value 1Off, retains value SCALE off
External Reference Off, Note 3EXT REF off Off, retains last value EXT REF off
Limits Off, Value 0wmmmmmm Off, retains last value Normal Display
Peak “PEAR off Off, retains last values PEAK off
Averaging Off AVG/(CAL) not on steady Off (2) AVG/(CAL) not on steady
Zero On, Cal
Memory Values Zero on Retains mode values and
state (4)
ZERO on (VDC,OHMS)
or off
Calibration Mode Note 4Note 4
Notes:
1. Re-selection of the same function sets autoranging (AUTO on), but retains all other mode values and states.
2. Disabling Average mode (by changing to anew function) sets filter mode F0 and sample setting 7. if the same function is re-
selected, the state of Average mode is not changed, and the existing filter mode and sample setting are retained.
3. The External Reference value is initialized to the multimeter software number whenever power-up or reset occurs. RECALL
EXT REF can then be used to display this number. Any subsequent activation of External Reference mode replaces the software
number with the actual external reference value.
4. The Calibration mode state is on or off solely dependent on the position of the rear panel Calibration Switch. Do not cycle power
on or off with this switch ON.
Calibration mode entries are applied to the reading as follows:
a. Gain correction factors are always applied (Calibration mode on or off).
b. Zero values are applied whenever Zero mode is on or off (Calibration mode on or off, VDC or OHMS selected). However, the
zero values used depend on the Calibration mode state.
Modes
Cal mode on, zero off
Cal mode on, zero on
Cal mode off, zero off
Cal mode off, zero on
Zero applied
Nothing
Permanent Zero
Permanent Zero
Permanent Zero and Temporary Zero
2-5

8505A
the VDC and VAC push buttons are pressed simultan-
eously and the RMS AC Converter module is installed.
2-28. Status annunciators light to signify various modes
of operation. Annunciators (as defined in parentheses)
light when any of the following modes are enabled: Peak
(PEAK), Scaling (SCALE), or External Reference
(EXT), Averaging (AVG/CAL), Offset (OFFSET),
Autoranging (AUTO), or VDC/ Ohms Zero (ZERO).
The FILTER annunciator lights (steadily) whenever the
slow filter is selected. The SAMPLE annunciator flashes
at the reading (display update) rate for sample settings
from 0through 7. The flash rate for setting 0, 1,or 2is very
rapid: SAMPLE appears steadily on. For sample settings
from 8through 17, the SAMPLE annunciator flashes at
the sample setting 7rate only. Since these higher sample
settings may require considerable time for adisplay
update, this feature is necessary to insure that the
operator is aware of a reading in progress. With a
distinctive display of HI, LO, or PASS, the Limits mode
requires no separate status annunciator.
2-29. OVERRANGE INDICATION
2-30. The measurement display presents adistinct
indication when overrange inputs are detected. An input
voltage exceeding the full scale value for the range
selected causes HHHHHH to flash. Overrange points for
each range are defined in Table 2-3.
2-31. WARNING INDICATION
2-32. When in the Scaling, External Reference, Offset
or Limits mode, there may be no readily discernible
display of the true measurement value. Therefore, asingle
His flashed in the exponent display when the voltage is
30V or higher at either the front panel input connections
or the rear panel external reference terminals.
NOTE
Flashing indicators in the digit or exponent
display are awarning only; they have no effect
on instrument operation.
2-33. ERROR CODES
2-34. Error codes offer considerable help in identifying
improper procedures or equipment configurations. These
codes are explained in Table 2-4.
2-35. INTERACTIVE PROGRAMMING INFOR-
MATION
2-36. The multimeter displays prompting messages
during STORE and RECALL operations. Whenever the
STORE button is pushed, the display responds with“7”.
The operator may now designate either the displayed
value or keystroked numerics as the programming entry.
If the displayed reading is being stored, pushing the
appropriate terminator button (FILTER, SAMPLE,
SCALING, HI OR LO -for LIMITS or OFFSET)
Table 2-3. Measurement Ranges
FUNCTION DECIMAL POINT POSITION
FOR RANGE INDICATED EXP OVERRANGE UNDERRANGE DIGITS
110 100 Ik
VDC 100 mV -3 200 mV —•-67a
IV 2V .17V 6Y2
10V 20V 1.7V 6V6
100V 128V12V 6V2
1000V 1200V 120V6'/a
VAC IV 2.5V —5’/a
10V 20V 1.875V 5%
100V 160V15V 5Va
1000V 1000V 120V 5Vi
100 fjA -6 312.5 /iA _5'/a
1mA -3 2.5 mA 234 fjA 5'/a
AAC 10 mA -3 20 mA 1.875 mA 5Vi
100 mA -3 160 mA 15 mA 5’/a
1A1.28 mA 120 mA 5Vi
ADC 100 fjA -6 250 //A —5Vi
tmA -3 2mA 187 aA5Vi
10 mA -3 16 mA 1.5 mA 5Vi
100 mA -3 128 mA 12 mA 5Vi
1A1.28A 124 mA 5Vi
OHMS 10 200 —5Vi
oo 2000 180 5'/a
IK +3 2kO 1800 6Vi
10K +3 25 kO 1.8 kO 6Vi
100k+3 250 kO 18 kO 6Vi
1M +6 4.1 MO 180 kO 572
10M +6 35 MO 1.8 MO 572
100M +6 265 MO 18 MO 5V?
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8505A
Table 2-4, Error Codes
MOMENTARY ERROR CONDITIONS
(The reading in progress is aborted, but multimeter operation is automatically restored with the next trigger. The
function annunciator remains on during amomentary error condition.)
CODE FAULT SOLUTION
Error 0VDC/Ohm Zero, zero attempted in wrong function
(not VDC or OHMS) or an overrange has been
entered.
Check function. Only VDC and OHMS are
permissible.
Error 1Store attempted during overload condition. Change to higher range or (if storing cal
correction factors) use lower value source.
Error 6Display overflow error. Check offset and scaling values.
Error 7External Reference error -voltage on one input
exceeds 20Vdc.
Revise external reference input.
Error 8Controller module is faulty. Power off; replace controller module.
Error bIllegal push button sequence in Calibration mode. Wait till display clears. Use correct sequence.
Error Cinvalid push-button sequence, or illegal value
entered.
Wait till display clears. Use correct sequence
or value within limits.
Error dCalibration Memory faulty or not installed. Occurs
when storing into, or recalling from, Calibration
Memory, or at power-up.
Replace or install Calibration Memory chip.
Error FCai Memory check-sum problem. Try new power-up. If necessary, reprogram Cal
Memory. Replacement of Calibration Memory
may be required.
Error HOhms connection problem. Verify that all connections are proper. Check
input fuses. Check input lead polarity in four-
terminal connections.
LATCHING ERROR CONDITIONS
(A valid function must be selected to restore multimeter operation
error condition.)
All function annunciators areoff during alatching
Error System error, usually appears at power-up or reset. Repeat power-up or reset.
Error 2Filter module faulty or not installed. Power off; replace or install filter module.
Error 3DC Signal Conditioner module faulty or not
installed.
Power off; replace or install DC Signal
Conditioner module.
Error 4OHMS, ADC, or AAC error. Check for improper input level. Check function
causing error indication. Applicable module
may need replacement or installation.
Error 5Analog to Digital Converter Module error. Power off; replace or install Analog to Digital
Converter module.
Error 9Function selection error. The function module
selected is faulty or not installed. VDC problem
causes Error 3.
Select valid function to clear error condition.
Power off; replace or install appropriate module.
Error EMore than one ac converter, or the wrong ac
converter, is installed. Also appears when
Calibration Memory module is installed.
Power off, remove one ac converter, or install
correct converter, or remove the Calibration
Memory module (the multimeter uses aseparate
Calibration Memory as part of the Controller).
2-7

8505A
completes the operation. The multimeter adopts both the
mode specified with the terminator and the value
previously displayed. If keystroked numerics are being
stored, the multimeter displays the digits as they are
entered from the front panel. Once all numbers for a
particular mode are entered, the appropriate terminator
button is pushed. For either method, the display now
resumes the measurement reading function or, if HI or
LO were specified as the terminator, begins reading HI,
LO, or PASS.
2-37. The RECALL button commands adisplay of a
stored factor or value. The procedure requires the
following two steps when recalling the offset value, the
scaling factor, the filter mode, the sample setting, or the
zero value:
1. Push the RECALL button (display responds
with T).
2. Push the appropriate terminator button
(OFFSET, SCALING, FILTER, SAMPLE or
ZERO). The respective value is displayed as long as
the terminator button is held depressed. Once the
terminator button is released, the multimeter
resumes operation; no mode or value is changed.
2-38. The following three push button steps are required
to recall alimit or peak value.
!. Push RECALL (display responds with “?”).
2. Then specify whether upper or lower limit or
peak is desired by pushing HI or LO (display
responds with “YES?”).
3. Finally, push the appropriate terminator
button (LIMITS or PEAK).
2-39. Front Panel Push Buttons
2-40. The multimeter employs 25 color-coded push
buttons on the front panel. Most of the push buttons
control more than one function. For example, many
mode control push buttons also serve as numeric entry
push buttons when used during a store operation. The
number of keystrokes required for any operation is kept
to aminimum. Refer to Figure 2-2 for adescription of
each push button and, where applicable, examples of
typical programming operations.
2-41. Operation of the multimeter is straightforward.
Preset measurement configurations are made at power-
up, reset, or function selection. Programmed values are
retained whenever the range or function is changed.
Desired mode changes are made independently following
aprogramming hierarchy of:
1. Measurement Parameters
2. Mathematic Operations
3. Special Operations
The FUNCTION push buttons allow selection of the analog measurement function. Available functions include: dc
volts (V DC), ac volts (V AC), dc current (A DC), ac current (A AC), and resistance (OHMS —two wire or four wire).
VDC
VAC
ADC
AAC
Push VDC for dc voltage measurements with 6'/
2-digit resolution (V DC annunciator lights). This
function is standard for the multimeter (no optional module required). Five ranges are available:
1000V, 100V, 10V, IV, and 100 mV.
Push V AC for ac voltage measurements with 5Y2-digit resolution (V AC annunciator lights). This
function can be used with either the -01 Averaging Converter or the -09A RMS Converter. Four
ranges are available: 1000V, 100V, 10V, and IV.
Push ADC for dc current measurements with 5V2-digit resolution (A DC annunciator lights). This
function can be used with the -03 Current Shunts module installed. Five ranges are available: 1A,
100 mA, 10 mA, 1mA, and 100 /jA.
Push AAC for ac current measurements with S'/^-digit resolution (A AC annunciator lights). This
function can be used when the -03 Current Shunts module and either the -01 Averaging Converter
or the -09A RMS Converter is installed. Available ranges are identical to those in the ADC
function.
Figure 2-2. Front Panel Push Buttons
2-8

8505A
OHMS
AUTO
MANUAL/
EXTERNAL
AUTO
i
t
Select the OHMS function to make resistance measurements (OHMS annunciator lights). The-02A
Ohms Converter must be installed. Eight resistance ranges are available: 100 MO, 10 MO, 1MO,
lOOkO, 10 kO, 1kO, 1000 and 100.
NOTE
Either two-wire or four-wire resistance measurements can be made. Refer to Measurement
Terminals and Controls.
The AUTO (trigger) push button selects the Auto Trigger mode. Aflashing SAMPLE annunciator
verifies Auto Trigger operation.
Initial use of the MANUAL/EXTERNAL push button disables the Auto Trigger mode (SAMPLE
annunciator stops flashing), enables the front panel Manual Triggering mode, and arms the
External Triggering mode. Each succeeding use of the MANUAL/EXTERNAL push button triggers
anew measurement: any reading already in progress is aborted and the new reading begun
immediately. The SAMPLE annunciator verifies that ameasurement has been triggered by flashing
once, or several times (if the sample-per-reading setting is greater than 7, 2exponent 7—128
samples). An external trigger applied through the rear panel external trigger jack similarly
commands anew reading. An external trigger applied simultaneously withafront pane! manual
trigger will be ignored. AUTO must be pushed to reenter the Auto Triggering mode.
AUTO RANGE toggles into/out of the Autoranging mode, changing the existing range if necessary.
When enabled (AUTO annunciator lighted), Autoranging automatically selects arange that
displays the measurement with maximum resolution.
Each use of this manual ranging push button selects the next higher available range, if AUTO
RANGE was previously activated, use of the uprange push button toggles out of Autoranging
(AUTO annunciator off) and steps to the next higher range. No range change is effected if the
multimeter is already in the highest range.
Use of the down-range push button causes the multimeter to toggle out of Autoranging (AUTO
annunciator off) and assume the next lower available range. Each successive use of the down-
range button selects the next lower range. This push button has no effect once the multimeter is in
the lowest available range.
Figure 2-2. Front Panel Push Buttons (cont)
2-9

8505A
RESET
LCL/RMT
EXT REF
LIMITS
PEAK
SAMPLE
CAREFUL: The RESET push button is powerful: all modes and stored values (other than calibration
factors) are lost if RESET is pressed. Once RESET is used, the multimeter assumes the Power-Up
configuration (without actual power loss). Temporary zero values are replaced with zero values
stored in Calibration Memory.
Depending on the remote interface being used, pushing the LCL/RMT button may cause one of
three multimeter responses.
1.
)If the -05 IEEE Interface is installed, LCL/RMT may be used to command local (front
panel) control only if the multimeter is already in remote (REMOTE annunciator
lighted). The push button has no effect if the multimeter is already in local.
2.
)If the -06 Bit Serial Interface or the -07 Parallel interface is installed. LCL/RMT may be
used to toggle into/out of local control at any time.
3.
)If no remote interface is installed, use of LCL/RMT causes alatching error condition.
MODIFIERS
EXT REF LIMITS PEAK SAMPLE FILTER
The EXT REF button toggles into/out of the External Reference mode. Either External Reference or
Scaling may be enabled: selection of one mode disables the other. After power-up or reset,
RECALL EXT REF can be used to identify the software version.
NOTE
The external reference voltage, applied through the rear input connector, can be read in the display
while EXT REF is held depressed.
The LIMITS push button toggles into/out of the Limits mode without changing stored limits values.
Adisplay of HI, LO, or PASS denotes use of the Limits mode.
The PEAK push button toggles into/out of the Peak mode. While in the Peak mode (PEAK
annunciator lighted), acontinually updated record of the highest and lowest reading values is
stored. These values are also held in memory after the mode is disabled. Reentry into the PEAK
mode erases previously recorded values and begins anew recording.
Different reading rates can be specified by selecting the number of samples averaged per
measurement. There are two methods for making this selection.
1.) The SAMPLE button can be pushed to toggle between two commonly used reading
rates: slow (1.9 readings-per-second, SAMPLE annunciator flashes slowly) and fast
(7.5 readings-per-second, SAMPLE annunciator flashes rapidly).
2-10

8505A
2.) Any of 18 different reading rates can be specified using the following push button
sequence:
STORE (0-17) SAMPLE
The SAMPLE annunciator now flashes at aspecified rate. For settings of 0-7, this rate is the reading
rate. For the slower settings of 8-17, asingle rate is preset to indicate a reading in progress.
Two methods are available for filter selection.
1
.
)By toggling the FILTER push button, the operator can select mode F (no mode number)
or FO (mode number 0).
2.
)The following sequence can be used to select any of the five filter modes:
STORE (mode number) FILTER
MODE
NUMBER FILTER TIMEOUT FILTER
LED
(blank) slow none on
0fast none off
1bypass none off
2slow 550 ms on
3fast 50 ms off
(No Mode Number is used for slow filter without timeout. Push STORE FILTER.)
The OFFSET push button can be used to toggle into/out of the Offset mode (OFFSET annunciator
lights). Two methods are available for simultaneously entering an offset value and activating the
Offset mode.
1.
)Anumeric value may be entered using astore sequence. For example, store an offset of
1.25 as follows:
STORE 1.25 OFFSET
2.
)Adisplayed reading can be stored as the offset value. Use the following sequence:
STORE OFFSET
NOTE
In some instances, the displayed value may not be an appropriate offset value. For
example, if the displayed value is being used to zero the multimeter, it is important to
verify that no other mathematic operations are in effect. In such acase, check that
OFFSET, SCALING, and EXT REF annunciators are all off before storing anew offset
value.
Figure 2-2. Front Panel Push Buttons (cont)
2-11

8505A
STORE
When the multimeter is in the Calibration Mode (AVG/(CAL) annunciator flashes), the
(CAL DATE) push button is used to enter six digits which either denote the date or
identify the multimeter by number. Refer to Calibration Mode later in this section.
The SCALING push button can be used to toggle into/out of the Scaling mode without
affecting any scaling value already stored. Either of the following two methods can be
used to store anew scaling factor and enable the Scaling mode:
NOTE
Verify that the displayed value is the desired scaling value. Any mathematic operations
(SCALING, EXT REF, OFFSET) already in effect must be cancelled if the actual
measurement is desired as the scaling value. To cancel any of these modes, toggle
SCALING, EXT REF, or OFFSET and verify that the respective annunciators are dark.
t. Use the following sequence to store the display as a scaling factor:
STORE SCALING
2. Numeric entry scaling factors must be programmed using the following
procedure:
STORE (numerics) SCALING
With either method, the Scaling mode is entered with the initial use of the SCALING
button.
The (CAL COR) push button is used when storing calibration factors for each function
and range, or when recalling uncorrected readings. Refer to Calibration Mode later in
this section.
STORE is used as afirst step in programming certain measurement parameters,
mathematic operations, or special operations. STORE is the only push button that can
activate the numeric entry keys. The multimeter prompts the second step by displaying
Following is alist of STORE operations:
Measurement Parameters:
0-17 SAMPLE
STORE 0,1, 2, 3or c,. T_D
2-12
Figure 2-2. Front Panel Push Buttons (cont)