Fluke Calibration Fluke Calibration 2638A/05 120 Manual

Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176

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2638A

HYDRA Series III Data Acquisition Unit

August 2014 Rev. 1, 5/16

© 2014-2016 Fluke Corporation. All rights reserved. Specifications are subject to change without notice.
All product names are trademarks of their respective companies.

Calibration Manual

Table of Contents

Title Page

Introduction ............................................................................................ 1

Contact Flu

Safety Information ................................................................................. 2

General Specifications .......................................................................... 5

Measurement Specifications ................................................................. 6

DC Voltage ........................................................................................ 6

DC Voltage Input Characteristics .................................................. 6

DC Voltage Accuracy .................................................................... 7

DC Voltage Additional Errors ......................................................... 7

AC Voltage ........................................................................................ 7

AC Voltage Input Characteristics ................................................... 8

AC Voltage Accuracy ..................................................................... 8

Additional Low Frequency Errors ...................................................... 8

DC Current ........................................................................................ 8

DC Current Input Characteristics ................................................... 9

DC Current Accuracy ..................................................................... 9

DC Current Additional Errors ......................................................... 9

AC Current ......................................................................................... 9

AC Current Input Characteristics ................................................... 9

AC Current Accuracy ..................................................................... 10

Additional Low Frequency Errors ...................................................... 10

Frequency .......................................................................................... 10

Resistance ......................................................................................... 10

Resistance Input Characteristics ................................................... 11

Resistance Accuracy ..................................................................... 11

Resistance Additional Errors ......................................................... 11

RTD ................................................................................................... 11

RTD Temperature Accuracy .......................................................... 12

RTD Measurement Characteristics ............................................... 12

Thermistor ......................................................................................... 12

Thermistor Temperature Accuracy ................................................ 12

Thermistor Measurement Characteristics ...................................... 13

Thermocouple .................................................................................... 13

Thermocouple Temperature Accuracy .......................................... 13

Thermocouple Measurement Characteristics ................................ 14

Digital I/O ........................................................................................... 14

ke ........................................................................................ 1

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Calibration Manual

Totalizer ............................................................................................. 14

Trigger ............................................................................................... 15

Alarm Output ..................................................................................... 15

2638A-100 Universal Input Module ....................................................... 15

General Maintenance ............................................................................ 16

If the Product Does Not Turn On ....................................................... 16

Clean the Product .............................................................................. 16

Replace the Line Power Fuse ........................................................... 16

Battery Replacement ......................................................................... 17

Memory and Factory Reset ............................................................... 18

Required Equipment .............................................................................. 19

Test Considerations .............................................................................. 21

Performance Tests ................................................................................ 21

Front Panel Test ................................................................................ 22

DC Volts Verification .......................................................................... 22

Volts AC and Frequency Verification ................................................. 24

4-Wire Ohms Verification ................................................................... 26

PRT Verification Steps ...................................................................... 27

Configure Resistance Display ........................................................... 27

Thermistor Verification Steps ............................................................ 28

Configure Resistance Display ........................................................... 28

DC Current Verification ...................................................................... 29

AC Current Verification Steps ............................................................ 31

2638A-100 Module Verification ......................................................... 32

Calibration Adjustment .......................................................................... 33

Unlock the Product ............................................................................ 33

Unlock the Product with a Remote Interface ..................................... 33

Reset the Admin Password ............................................................... 34

Disassembly ...................................................................................... 35

Change the Calibration Date Remotely ............................................. 37

“Mainframe” Adjustment Process ...................................................... 37

Remote Commands for Calibration ....................................................... 43

Remote Programming Examples ....................................................... 44

Start a Full Calibration ....................................................................... 44

Calibrate 1 V DC Range only ............................................................ 45

Write Calibration Date to a Module .................................................... 45

Command References ....................................................................... 46

User-Replaceable Parts and Accessories ............................................. 51

ii

Introduction

The Fluke 2638A HYDRA Series III Data Acquisition Unit (the Product or
Instrument) is a 67 analog channel bench-top data logger that measures and
records dc volts, ac volts, dc current, ac current, resistance, frequency, and
temperature. See the Specifications section for information on the types and
ranges of the measurement inputs the Product can accept.

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Safety Information

Symbol Description Symbol Description

A Warning identifies conditions and procedures that are dangerous to the user.
A Caution identifies conditions and procedures that can cause damage to the
Product or the equipment under test.

See Table 1 for a list of symbols used in this manual and on the Product.

Table 1. Symbols

W

X




or




Ã







~

Risk of Danger. Important
information. See Manual.

Hazardous voltage. Voltage
>30 V dc or ac peak might be
present.

Earth ground.  Digital signal

AC or DC (Alternating or Direct
Current)

Recycle.

Conforms to relevant South
Korean EMC Standards.

Measurement Category II is applicable to test and measuring circuits connected directly to
utilization points (socket outlets and similar points) of the low-voltage MAINS installation.

Measurement Category III is applicable to test and measuring circuits connected to the
distribution part of the building’s low-voltage MAINS installation.

Measurement Category IV is applicable to test and measuring circuits connected at the
source of the building’s low-voltage MAINS installation.

This product complies with the WEEE Directive marking requirements. The affixed label
indicates that you must not discard this electrical/electronic product in domestic household
waste. Product Category: With reference to the equipment types in the WEEE Directive
Annex I, this product is classed as category 9 "Monitoring and Control Instrumentation”
product. Do not dispose of this product as unsorted municipal waste.

 DC (Direct Current)

 AC or DC (Alternating or Direct Current)

T

+

Double insulated

Power ON / OFF

P Conforms to European Union directives.

2

HYDRA Series III Data Acquisition Unit

Safety Information

WXWarning

To prevent possible electrical shock, fire, or personal injury:

• Read all safety information before you use the Product.

• Carefully read all instructions.

• Use the Product only as specified, or the protection supplied

by the Product can be compromised.

• Examine the case before you use the Product. Look for cracks
or missing plastic. Carefully look at the insulation around the
terminals.

• Do not use the Product if it operates incorrectly.

• Do not use the Product if it is damaged.

• Disable the Product if it is damaged.

• Use only the mains power cord and connector approved for

the voltage and plug configuration in your country and rated
for the Product.

• Replace the mains power cord if the insulation is damaged or
if the insulation shows signs of wear.

• Make sure the ground conductor in the mains power cord is
connected to a protective earth ground. Disruption of the
protective earth could put voltage on the chassis that could
cause death.

• Do not put the Product where access to the mains power cord
is blocked.

• Use only correct measurement category (CAT), voltage, and
amperage rated probes, test leads, and adapters for the
measurement.

• Use only cables with correct voltage ratings.

• Do not use test leads if they are damaged. Examine the test

leads for damaged insulation and measure a known voltage.

• Do not exceed the Measurement Category (CAT) rating of the
lowest rated individual component of a Product, probe, or
accessory.

• Keep fingers behind the finger guards on the probes.

• Do not apply more than the rated voltage, between the

terminals or between each terminal and earth ground.

• Do not touch voltages >30 V ac rms, 42 V ac peak, or 60 V dc.

• Limit operation to the specified measurement category,

voltage, or amperage ratings.

• Measure a known voltage first to make sure that the Product
operates correctly.

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2638A

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• Consider all accessible channels to be hazardous live and an
electric shock hazard if any channel is connected to a
hazardous voltage source.

• Do not remove, touch, or change the internal wiring of
hazardous inputs until the input source is turned off.

• Remove inputs from hazardous voltage sources before an
input module is opened.

• Use the correct terminals, function, and range for
measurements.

• Use this Product indoors only.

• Do not use the Product around explosive gas, vapor, or in

damp or wet environments.

4

HYDRA Series III Data Acquisition Unit

General Specifications

General Specifications

Mains Voltage

100 V Setting ...................................................... 90 V to 110 V

120 V Setting ...................................................... 108 V to 132 V

220 V Setting ...................................................... 198 V to 242 V

240 V Setting ...................................................... 216 V to 264 V

Frequency .............................................................. 47 Hz to 440 Hz

Power Consumption ............................................. 36 VA peak (24 W average)

Environment Temperature

Operating ............................................................ 0 °C to 50 °C

Full accuracy ....................................................... 18 °C to 28 °C

Storage ............................................................... -20 °C to 70 °C

Warm-up ............................................................. 1 hour to full accuracy specifications

Relative Humidity (non-condensing)

Operating ............................................................ 0 °C to 28 °C <90 %

28 °C to 40 °C <75 %
40 °C to 50 °C <45 %

Storage ............................................................... -20 °C to 70 °C <95 %

Altitude

Operating ............................................................ 2,000 m

Storage ............................................................... 12,000 m

Channel Capacity

Total analog channels ........................................ 67

Voltage/resistance channels ............................... 61

Current channels ................................................ 7

Digital I/O ............................................................ 8 bits

Totalizer .............................................................. 1

Alarm outputs...................................................... 6

Trigger input ........................................................ 1

Channel Capacity: 2638A/05

Total analog channels ......................................... 23

Voltage/resistance channels ............................... 21

Current channels ................................................ 2

Safety Protection

Mains Input ......................................................... IEC 61010-1, Overvoltage Category II, Pollution Degree 2

Measurement Front Panel .................................. IEC 61010-2-030: CAT II 300 V

Measurement Rear Panel ................................... IEC 61010-2-030: CAT II 150 V CAT II, 250 V rms with maximum

Electromagnetic Compatibility (EMC)

International ........................................................ IEC 61326-1: Basic Electromagnetic Environment

transient voltage of 1000 V peak. These terminals are not intended for
connection to mains voltage above 150 V without external transient
suppression. The maximum input that can be applied between rear­module terminals or between any rear-module terminal and earth
ground is 250 V dc or ac rms.

CISPR 11: Group 1, Class A

Group 1: Equipment has intentionally generated and/or uses
conductively-coupled radio frequency energy that is necessary for
the internal function of the equipment itself.

Class A: Equipment is suitable for use in all establishments other
than domestic and those directly connected to a low-voltage power
supply network that supplies buildings used for domestic purposes.
There may be potential difficulties in ensuring electromagnetic
compatibility in other environments due to conducted and radiated
disturbances.

Emissions that exceed the levels required by CISPR 11 can occur
when the equipment is connected to a test object.

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2638A

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Korea (KCC) ....................................................... Class A Equipment (Industrial Broadcasting & Communication

USA (FCC) .......................................................... 47 CFR 15 subpart B. This product is considered an exempt device per

Math Channels

Number of channels............................................ 20

Operations .......................................................... sum, difference, multiply, divide, polynomial, power, square root,

Triggers .................................................................. interval, external (trigger input), alarm, remote (bus), manual

Battery life ............................................................. 5 years

Memory

Scan data RAM................................................... 75,000 readings with timestamp

Data/Setup flash memory ................................... 20 MB

Non-volatile memory life ..................................... 5 years

USB Host Port

Standard ............................................................. 2.0, full speed

Connector type ................................................... Type A

Function .............................................................. Memory

File system .......................................................... FAT32

Memory capacity................................................. 32 GB

USB Device Port

Connector type ................................................... Type B

Class ................................................................... Instrument

Function .............................................................. Control and data transfer

Command protocol ............................................. SCPI

LAN

Function .............................................................. Control and data transfer

Network protocols ............................................... Ethernet 10/100, TCP/IP

Command protocol ............................................. SCPI

Dimensions

Height ................................................................. 150 mm

Width ................................................................... 245 mm

Depth .................................................................. 385 mm

Weight ................................................................. 6 kg (typical configuration)

Shipping Weight.................................................. 9.5 kg (typical configuration)

Conformity ............................................................. CE, CSA, IEC 61010 3

Equipment)

Class A: Equipment meets requirements for industrial
electromagnetic wave equipment and the seller or user should take
notice of it. This equipment is intended for use in business
environments and not to be used in homes.

clause 15.103.

reciprocal, exponential, logarithm, absolute value, average, maximum,
minimum

rd

ed.

6

Measurement Specifications

Accuracy specifications generally are valid for 6 ½ digit resolution mode (unless otherwise noted) for front panel input
(Channel 001), after a minimum of 1-hour warm-up, and within an environment temperature range of 18 °C to 28 °C.
24-hour specifications are relative to calibration standards and assume a controlled electromagnetic environment per EN

61326. The confidence level for accuracy specifications is 99 % within 1 year of calibration (unless otherwise noted).
Scan rate (typical, depending on function and range)

Fast ..................................................................... 46 channels per second max (0.02 seconds per channel)

Medium ............................................................... 10 channels per second (0.1 seconds per channel)

Slow .................................................................... 2 channels per second (0.5 seconds per channel)

Display Resolution ................................................ 4 ½ to 6 ½ digits, depending on Sample Rate or NPLC

DC Voltage

Maximum Input ...................................................... 300 V on any range

Common Mode Rejection ..................................... 140 dB at 50 Hz or 60 Hz (1 kΩ unbalance for NPLC of 1 or greater,

±500 V peak maximum in the low lead)

Normal Mode Rejection ........................................ 55 dB for NPLC of 1 or greater and power-line frequency ±0.1 %,

±20 % of range peak maximum

Measurement Method ........................................... Multi-ramp A/D

A/D Linearity .......................................................... 2 ppm of measurement + 1 ppm off range

HYDRA Series III Data Acquisition Unit

Measurement Specifications

Input Bias Current ................................................. <30 pA at 25 °C

DC Voltage Input Characteristics

Resolution

Range Resolution

100 mV 100.0000 mV

1 V 1.000000 V

10 V 10.00000 V 1 mV
100 V 100.0000 V 10 mV 1 mV
300 V 300.000 V 100 mV 10 mV 1 mV

Note:
Input beyond ±12 V is clamped. The clamp current is up to 3 mA. 10 MΩ is default input impedance.

Fast

4½ Digits

10 μV 1 μV 0.1 μV

100 μV 10 μV 1 μV

Medium

5 ½ Digits

100 μV 10 μV

6 ½ Digits

100 μV 10 MΩ ±1 %

Slow

Input Impedance

10 MΩ or >10 GΩ
10 MΩ or >10 GΩ
10 MΩ or >10 GΩ

10 MΩ ±1 %

[1]

[1]

[1]

DC Voltage Accuracy

Accuracy is given as ± (% measurement + % of range).

Range

100 mV 0.0025 % + 0.003 % 0.0025 % + 0.0035 % 0.0037 % + 0.0035 % 0.0005 % + 0.0005 %

1 V 0.0018 % + 0.0006 % 0.0018 % + 0.0007 % 0.0025 % + 0.0007 % 0.0005 % + 0.0001 %

10 V 0.0013 % + 0.0004 % 0.0018 % + 0.0005 % 0.0024 % + 0.0005 % 0.0005 % + 0.0001 %
100 V 0.0018 % + 0.0006 % 0.0027 % + 0.0006 % 0.0038 % + 0.0006 % 0.0005 % + 0.0001 %
300 V 0.0018 % + 0.002 % 0.0031 % + 0.002 % 0.0041 % + 0.002 % 0.0005 % + 0.0003 %

Notes:

• For conducted disturbances on mains input >1 V from 10 MHz to 20 MHz, add 0.02 % of range. For disturbances

>3 V, accuracy is unspecified.

• For radiated disturbances >1V/m from 450 MHz to 550 MHz, add 0.02 % of range. For disturbances > 3 V/m,

accuracy is unspecified.

24 Hour

(23 ±1 °C)

90 Days

(23 ±5 °C)

1 Year

(23 ±5 °C)

T.C./ °C

Outside

18 °C to 28 °C

DC Voltage Additional Errors

Digits NPLC Ch. x01 – x20

6 ½ 200
6 ½
6 ½
5 ½ 1 (Medium)
4 ½ 0.2 (Fast) ­4 ½ 0.02 -

100

10 (Slow)

add 2 μV
add 2 μV
add 2 μV
add 2 μV

Additional NPLC Noise

Error

-

-

-

add 0.0008 % of range

add 0.002 % of range + 12 μV
add 0.014 % of range + 17 μV

AC Voltage

AC voltage specifications are for ac sine wave signals >5 % of range. For inputs from 1 % to 5 % of range and <50 kHz,
add an additional error of 0.1 % of range. For 50 kHz to 100 kHz, add 0.13 % of range.

Maximum Input ...................................................... 300 V rms or 425 V peak or 3 × 10

less) for any range.

Measurement Method ........................................... AC-coupled true-rms. Measures the ac component of input with up to

300 V dc bias on any range.

AC Filter Bandwidth:

Slow .................................................................... 20 Hz

Fast ..................................................................... 200 Hz

Maximum Crest Factor ......................................... 5:1 at full scale

7

volts-Hertz product (whichever is

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Calibration Manual

Additional Crest Factor Errors ............................ Crest factor 1-2, 0.05 % of full scale

Crest factor 2-3, 0.2 % of full scale
Crest factor 3-4, 0.4 % of full scale
Crest factor 4-5, 0.5 % of full scale

AC Voltage Input Characteristics

Range Resolution

100 mV 100.0000 mV

AC Voltage Accuracy

Accuracy is given as ± (% measurement + % of range).

Resolution

4 ½

Digits

10 μV 1 μV 0.1 μV

1 V 1.000000 V

10 V 10.00000 V 1 mV 100 µV
100 V 100.0000 V 10 mV 1 mV
300 V 300.000 V 100 mV 10 mV 1 mV

100 μV 10 μV 1 μV

5 ½

Digits

6 ½

Digits

10 μV

100 μV

Input Impedance

1 MΩ ±2 % shunted by 150 pF

Range Frequency

20 Hz to 20 kHz 0.1 % + 0.05 % 0.11 % + 0.05 % 0.11 % + 0.05 % 0.01 % + 0.005 %

100 mV

1 V

10 V

100 V

300 V

Note:
For conducted disturbances on mains input >1 V from 10 MHz to 40 MHz, add 0.02 % of range. For disturbances >3 V,

accuracy is unspecified.

20 kHz to 50 kHz 0.2 % + 0.05 % 0.22 % + 0.05 % 0.22 % + 0.05 % 0.01 % + 0.005 %

50 kHz to 100 kHz 0.55 % + 0.08 % 0.6 % + 0.08 % 0.6 % + 0.08 % 0.05 % + 0.01 %

20 Hz to 20 kHz 0.1 % + 0.05 % 0.11 % + 0.05 % 0.11 % + 0.05 % 0.01 % + 0.005 %

20 kHz to 50 kHz 0.2 % + 0.05 % 0.22 % + 0.05 % 0.22 % + 0.05 % 0.01 % + 0.005 %

50 kHz to 100 kHz 0.55 % + 0.08 % 0.6 % + 0.08 % 0.6 % + 0.08 % 0.05 % + 0.01 %

20 Hz to 20 kHz 0.1 % + 0.05 % 0.11 % + 0.05 % 0.11 % + 0.05 % 0.01 % + 0.005 %

20 kHz to 50 kHz 0.2 % + 0.05 % 0.22 % + 0.05 % 0.22 % + 0.05 % 0.01 % + 0.005 %

50 kHz to 100 kHz 0.55 % + 0.08 % 0.6 % + 0.08 % 0.6 % + 0.08 % 0.05 % + 0.01 %

20 Hz to 20 kHz 0.1 % + 0.05 % 0.11 % + 0.05 % 0.11 % + 0.05 % 0.01 % + 0.005 %

20 kHz to 50 kHz 0.2 % + 0.05 % 0.22 % + 0.05 % 0.22 % + 0.05 % 0.01 % + 0.005 %

50 kHz to 100 kHz 0.55 % + 0.08 % 0.6 % + 0.08 % 0.6 % + 0.08 % 0.05 % + 0.01 %

20 Hz to 20 kHz 0.1 % + 0.05 % 0.11 % + 0.05 % 0.11 % + 0.05 % 0.01 % + 0.005 %

20 kHz to 50 kHz 0.2 % + 0.05 % 0.22 % + 0.05 % 0.22 % + 0.05 % 0.01 % + 0.005 %

50 kHz to 100 kHz 0.55 % + 0.27 % 0.6 % + 0.27 % 0.6 % + 0.27 % 0.05 % + 0.03 %

24 Hour

(23 ±1 °C)

90 Days

(23 ±5 °C)

1 Year

(23 ±5 °C)

T.C./ °C
Outside

18 °C to 28 °C

Additional Low Frequency Errors

Error is stated as % of reading.

Frequency

20 Hz to 40 Hz 0 % −

40 Hz to 100 Hz

100 Hz to 200 Hz

200 Hz to 1 kHz

>1 kHz

20 Hz 200 Hz

0 % 0.55 %
0 %
0 %

0 %

AC Filte

0.2 %

0.02 %
0 %

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HYDRA Series III Data Acquisition Unit

Measurement Specifications

DC Current

Input Protection .................................................... 0.15 A / 600 V Resettable PTC

DC Current Input Characteristics

Resolution

Range Resolution

Fast

4½

Digits

100 μA

1 mA 1.000000 mA 100 nA 10 nA 1 nA

10 mA 10.00000 mA

100 mA 100.0000 mA

100.0000 µA 10 nA 1 nA 0.1 nA

1 μA

10 μA 1 μA

Medium

5 ½

Digits

100 nA 10 nA

Slow

Digits

100 nA

6 ½

Reference

Resistance

(Ohms)

1k Ω

1k Ω
10 Ω
10 Ω

DC Current Accuracy

Accuracy is given as ± (% measurement + % of range).

Range

100 μA

1 mA 0.005 % + 0.001 % 0.015 % + 0.0011 % 0.015 % + 0.0011 % 0.002 % + 0.001 %

10 mA 0.005 % + 0.003 % 0.015 % + 0.0035 % 0.015 % + 0.0035 % 0.002 % + 0.001 %

100 mA 0.005 % + 0.001 % 0.015 % + 0.0035 % 0.015 % + 0.0035 % 0.002 % + 0.001 %

24 Hour

(23 ±1 °C)

0.005 % + 0.003 % 0.015 % + 0.0035 % 0.015 % + 0.0035 % 0.002 % + 0.001 %

90 Days

(23 ±5 °C)

1 Year

(23 ±5 °C)

18 °C to 28 °C

DC Current Additional Errors

Digits NPLC

6 ½ 200 - ­6 ½ 100 - ­6 ½ 10 (Slow) - ­5 ½ 1 (Medium) 0.0008 % of range 0.0008 % of range
4 ½ 0.2 (Fast) 0.002 % of range + 1.2 µA 0.002 % of range + 12 nA
4 ½ 0.02 0.014 % of range + 1.7 µA 0.014 % of range + 17 nA

Additional NPLC Noise Error

for 10 mA, 100 mA

Additional NPLC Noise

Error for 100 µA, 1 mA

Burden
Voltage

<1 mV
<1 mV
<1 mV
<1 mV

T.C./ °C

Outside

AC Current

Input Protection .................................................... 0.15 A / 600 V resettable PTC

Measurement Method ........................................... AC-coupled true-rms, dc-coupled to the shunt (no blocking capacitor).

AC Filter Bandwidth:

Slow .................................................................... 20 Hz

Fast ..................................................................... 200 Hz

Maximum Crest Factor ......................................... 5:1 at full scale

Additional Crest Factor Errors ............................ Crest factor 1-2, 0.05 % of full scale

Crest factor 2-3, 0.2 % of full scale
Crest factor 3-4, 0.4 % of full scale
Crest factor 4-5, 0.5 % of full scale

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AC Current Input Characteristics

Resolution

Range Resolution

100 μA

1 mA 1.000000 mA 100 nA 10 nA 1 nA

10 mA 10.00000 mA

100 mA 100.0000 mA

100.0000 µA 10 nA 1 nA 0.1 nA

4 ½

Digits

1 μA

10 μA 1 μA

5 ½

Digits

100 nA 10 nA

6 ½

Digits

100 nA

Reference

Resistance

1 kΩ
1 kΩ
10 Ω
10 Ω

Burden
Voltage

<10 mV (RMS)
<10 mV (RMS)
<20 mV (RMS)
<50 mV (RMS)

AC Current Accuracy

Accuracy is given as ± (% measurement + % of range). Basic accuracy specification is for a sinusoidal signal with
amplitude greater than 5 % of range. For input signals between 1 % to 5 % of range, add 0.1 % of range.

Range Frequency

100 μA

1 mA 20 Hz to 2 kHz 0.2 % + 0.06 % 0.25 % + 0.06 % 0.3 % + 0.06 % 0.015 % + 0.005 %

10 mA 20 Hz to 2 kHz 0.2 % + 0.06 % 0.25 % + 0.06 % 0.3 % + 0.06 % 0.015 % + 0.005 %

100 mA 20 Hz to 2 kHz 0.2 % + 0.06 % 0.25 % + 0.06 % 0.3 % + 0.06 % 0.015 % + 0.005 %

20 Hz to 2 kHz

24 Hour

(23 ±1 °C)

0.2 % + 0.06 % 0.25 % + 0.06 % 0.3 % + 0.06 % 0.015 % + 0.005 %

90 Days

(23 ±5 °C)

1 Year

(23 ±5 °C)

T.C./ °C Outside

18 °C to 28 °C

Additional Low Frequency Errors

Error is stated as % of reading.

Frequency

20 Hz to 40 Hz

40 Hz to 100 Hz

100 Hz to 200 Hz

200 Hz to 1 kHz

>1 kHz

AC Filte

20 Hz 200 Hz

0 %
0 %
0 %
0 %
0 %

−

0.55 %

0.2 %

0.02 %
0 %

Frequency

Gate Times ............................................................. 100 milliseconds to 1 second.

Measurement Method ........................................... Flexible counting technique. AC-coupled input using the ac voltage

Settling Considerations........................................ When measuring frequency after a dc offset voltage change, errors

Measurement Considerations.............................. To minimize measurement errors, shield inputs from external noise

measurement function.

may occur. For the most accurate measurement, wait up to 1 second
for the input blocking capacitor to settle.

when measuring low-voltage, low-frequency signals.

Frequency Accuracy

Accuracy is given as ± % of measurement.

Range Frequency

100 mV to

[1] [2]

300 V

[1] Input >100 mV. For 10 mV to 100 mV, multiply percent measurement error by 10.
[2] Limited to 3 x 10

20 Hz to 40 Hz 0.03 % 0.03 % 0.03 % 0.001 %

40 Hz to 1 MHz

7

volt-Hertz

24 Hour

(23 ±1 °C)

0.006 % 0.01 % 0.01 % 0.001 %

90 Days

(23 ±5 °C)

1 Year

(23 ±5 °C)

T.C./ °C
Outside 18
°C to 28 °C

Resistance

Measurement Method ........................................... Current source referenced to LO input.

Max. Lead Resistance (4-wire ohms) .................. 10 Ω per lead for 100 Ω, 1 kΩ ranges. 1 kΩ per lead on all other

Input Protection .................................................... 300 V on all ranges.

ranges.

10

HYDRA Series III Data Acquisition Unit

Measurement Specifications

Resistance Input Characteristics

Resolution

Range Resolution

100 Ω 100.0000 Ω 10 mΩ 1 mΩ 0.1 mΩ

1 kΩ 1.000000 kΩ 100 mΩ 10 mΩ 1 mΩ

10 kΩ 10.00000 kΩ 1 Ω 100 mΩ 10 mΩ

100 kΩ 100.0000 kΩ 10 Ω 1 Ω 100 mΩ

1 MΩ 1.000000 MΩ 100 Ω 10 Ω 1 Ω

10 MΩ 10.00000 MΩ 1 kΩ 100 Ω 10 Ω

100 MΩ 100.0000 MΩ 10 kΩ 1 kΩ 100 Ω

Fast

4½ Digits

Medium

5 ½ Digits

Slow

6 ½ Digits

Source Current

1 mA / 4 V
1 mA / 4 V

100 µA / 6 V

100 µA / 12 V

10 µA / 12 V

1 µA / 12 V

0.1 µA / 12 V

Resistance Accuracy

Accuracy is given as ± (% measurement + % of range). Basic accuracy specification is for 4-wire resistance. For 2-wire
resistance add 0.02 Ω internal resistance if using Channel 1 or 1.5 Ω if using channels x01 through x20, and add external
lead wire resistance.

Range

100 Ω

1 kΩ

10 kΩ

100 kΩ

1 MΩ

10 MΩ

100 MΩ

Note:
For conducted disturbances on mains input >1 V from 10 MHz to 40 MHz, add 0.6 % of range. For disturbances >3 V,

accuracy is unspecified.

24 Hour

(23 ±1 °C)

0.003 % + 0.003 % 0.008 % + 0.004 % 0.01 % + 0.004 % 0.0006 % + 0.0005 %

0.002 % + 0.0005 % 0.008 % + 0.001 % 0.01 % + 0.001 % 0.0006 % + 0.0001 %

0.002 % + 0.0005 % 0.008 % + 0.001 % 0.01 % + 0.001 % 0.0006 % + 0.0001 %

0.002 % + 0.0005 % 0.008 % + 0.001 % 0.01 % + 0.001 % 0.0006 % + 0.0001 %

0.002 % + 0.001 % 0.008 % + 0.001 % 0.01 % + 0.001 % 0.001 % + 0.0002 %

0.015 % + 0.001 % 0.02 % + 0.001 % 0.04 % + 0.001 % 0.003 % + 0.0004 %

0.3 % + 0.01 % 0.8 % + 0.01 % 0.8 % + 0.01 % 0.05 % + 0.002 %

90 Days

(23 ±5 °C)

1 Year

(23 ±5 °C)

T.C./ °C

Outside 18 °C

to 28 °C

Resistance Additional Errors

Digits NPLC Additional NPLC Noise Error

6 ½ 200 0 % of range
6 ½ 100 0 % of range
6 ½ 10 (Slow) 0 % of range
5 ½ 1 (Medium) 0.0008 % of range
4 ½ 0.2 (Fast)(only for 2-wire)
4 ½ 0.02 (only for 2-wire)

0.002 % of range + 12 mΩ

0.01 % of range + 17 mΩ

RTD

Temperature Range .............................................. -200 °C to 1200 °C (depending on the sensor)

Resistance Range ................................................. 0 Ω to 4 kΩ

Maximum Lead Resistance (4-wire Ω) ................ 2.5 % of range per lead for 400 Ω and 4 kΩ ranges

Sample Rate

Slow .................................................................... 10 PLC

Medium ............................................................... 2 PLC

Fast ..................................................................... 1 PLC

11

2638A

Calibration Manual

RTD Temperature Accuracy

Accuracy is for 4-wire 100 Ω nominal RTD, using the slow sample rate. With 3-wire PRT/RTD add 0.015 °C if using
Channel 1, or add 0.15 °C internal resistance mismatch to the accuracy specification if using channels x01 through x20,
and add external lead wire resistance mismatch. When using medium or fast sample rate (NPLC <10), add the number
given in the table to the accuracy specification. If the environment temperature is outside the specified range, multiply the
Temperature Coefficient number by the temperature deviation and add to the accuracy specification. Linear interpolation
may be used between points in the table. Specifications do not include sensor accuracy. The practical range of
temperature measurement depends on the sensor and characterization.

Temperature Accuracy

-200 °C 0.016 °C add 0.02 °C 0.0026 °C
0 °C 0.038 °C add 0.02 °C 0.0041 °C

300 °C 0.073 °C add 0.03 °C 0.0063 °C
600 °C 0.113 °C add 0.03 °C 0.0089 °C

Note:

For conducted disturbances on mains input >1 V from 10 MHz to 40 MHz, add 0.2 Celsius. For disturbances >3 V,
accuracy is unspecified.

Medium/Fast Sample

Rate (NPLC <10)

T.C./ °C Outside

18 °C to 28 °C

RTD Measurement Characteristics

Temperature Display Resolution

Range

0 Ω to 400 Ω

400 Ω to 4 kΩ

Slow

Sample Rate

0.001 °C 0.01 °C

0.001 °C 0.01 °C

Medium/Fast
Sample Rate

Source Current

1 mA

0.1 mA

Thermistor

Temperature Range .............................................. -200 °C to 400 °C (depending on the sensor)

Resistance Range ................................................. 0 Ω to 1 MΩ

Sample Rate

Slow .................................................................... 10 PLC

Medium ............................................................... 2 PLC

Fast ..................................................................... 1 PLC

12

Thermistor Temperature Accuracy

Accuracy specifications are for a 4-wire thermistor using medium or slow sample rate. With 2-wire thermistor add the
number given in the table to the accuracy specification for internal resistance. When using fast sample rate (NPLC <10),
multiply the accuracy specification by 3. If the environment temperature is outside the specified range, increase the
accuracy specification by 25 % for every 1 °C outside the specified environment temperature range. Specifications do not
include sensor accuracy. The practical range of temperature measurement depends on the sensor.

Accuracy

Temperature

-40 °C 0.002 °C 0.007 °C 0.007 °C add 0.002 °C
0 °C 0.005 °C 0.004 °C 0.003 °C add 0.004 °C

25 °C 0.013 °C 0.007 °C 0.005 °C add 0.016 °C

50 °C 0.019 °C 0.01 °C 0.011 °C add 0.05 °C
100 °C 0.116 °C 0.054 °C 0.026 °C add 0.34 °C
150 °C 0.527 °C 0.239 °C 0.1 °C add 1.7 °C

Note:

For conducted disturbances on mains input >1 V from 10 MHz to 40 MHz, add 0.2 Celsius. For disturbances >3 V,
accuracy is unspecified.

2.2 kΩ

thermistor

5 kΩ

thermistor

10 kΩ

thermistor

2-wire

HYDRA Series III Data Acquisition Unit

Measurement Specifications

Thermistor Measurement Characteristics

Temperature Display Resolution

Range

0 Ω to 98 kΩ

95 kΩ to 1 MΩ

Slow

Sample Rate

0.001 °C 0.01 °C

0.001 °C 0.01 °C

Medium/Fast
Sample Rate

Source Current

10 μA

1 μA

Thermocouple

Temperature Range .............................................. -270 °C to 2315 °C (depending on the sensor)

Voltage Range ....................................................... -15 mV to 100 mV

Sample Rate

Slow .................................................................... 10 PLC

Medium ............................................................... 2 PLC

Fast ..................................................................... 1 PLC

Thermocouple Temperature Accuracy

Accuracy specifications apply using a slow sample rate. When using a medium or fast sample rate (NPLC < 10), increase
the accuracy specification by 25 %. If the environment temperature is outside the specified range, increase the accuracy
specification by 12 % for every 1 °C outside the specified environment temperature range. Accuracy with fixed/external
CJC does not include the accuracy of the reference junction temperature. Linear interpolation may be used between
points in the table. Specifications do not include sensor accuracy. The practical range of temperature measurement
depends on the sensor.

Type

(Range)

K

-270 °C to 1372 °C

T

-270 °C to 400 °C

R

-50 °C to 1768 °C

S

-50 °C to 1768 °C

J

-210 °C to 1200 °C

N

-270 °C to 1300 °C

E

-270 °C to 1000 °C

Temperature

-200 °C
0 °C

1000 °C

-200 °C
0 °C

200 °C
400 °C

0 °C

300 °C
1200 °C
1600 °C

0 °C

300 °C
1200 °C
1600 °C

-200 °C
0 °C

1000 °C

-200 °C
0 °C

500 °C

1000 °C

-200 °C
0 °C

300 °C
700 °C

Accuracy

Fixed / External CJC Internal CJC

Channel 1 Ch. x01 – x20 Ch. x01 – x20

0.28 °C

0.10 °C

0.14 °C

0.27 °C

0.10 °C

0.08 °C

0.08 °C

0.76 °C

0.42 °C

0.33 °C

0.34 °C

0.74 °C

0.45 °C

0.37 °C

0.39 °C

0.20 °C

0.08 °C

0.11 °C

0.42 °C

0.15 °C

0.12 °C

0.14 °C

0.17 °C

0.07 °C

0.06 °C

0.08 °C

0.41 °C

0.15 °C

0.20 °C

0.40 °C

0.15 °C

0.12 °C

0.11 °C

1.13 °C

0.63 °C

0.47 °C

0.49 °C

1.11 °C

0.67 °C

0.54 °C

0.56 °C

0.29 °C

0.12 °C

0.14 °C

0.62 °C

0.23 °C

0.17 °C

0.19 °C

0.25 °C

0.10 °C

0.09 °C

0.10 °C

1.60 °C

0.62 °C

0.64 °C

1.60 °C

0.65 °C

0.47 °C

0.41 °C

1.28 °C

0.71 °C

0.52 °C

0.54 °C

1.26 °C

0.76 °C

0.60 °C

0.63 °C

1.41 °C

0.61 °C

0.53 °C

1.69 °C

0.64 °C

0.44 °C

0.45 °C

1.42 °C

0.61 °C

0.46 °C

0.45 °C

13

2638A

Calibration Manual

B

100 °C to 1820 °C

C

0 °C to 2315 °C

D

0 °C to 2315 °C

G

0 °C to 2315 °C

L

-200 °C to 900 °C

M

-50 °C to 1410 °C

U

-200 °C to 600 °C

W

0 °C to 2315 °C

300 °C

600 °C
1200 °C
1600 °C

600 °C
1200 °C
2000 °C

600 °C
1200 °C
2000 °C

600 °C
1200 °C
2000 °C

-200 °C
0 °C

800 °C

0 °C

500 °C

1000 °C

-200 °C
0 °C

400 °C

600 °C
1200 °C
2000 °C

1.32 °C

0.68 °C

0.41 °C

0.38 °C

0.23 °C

0.28 °C

0.44 °C

0.22 °C

0.26 °C

0.39 °C

0.24 °C

0.22 °C

0.33 °C

0.13 °C

0.08 °C

0.09 °C

0.11 °C

0.10 °C

0.10 °C

0.25 °C

0.10 °C

0.08 °C

0.24 °C

0.22 °C

0.33 °C

1.97 °C

1.02 °C

0.60 °C

0.55 °C

0.33 °C

0.40 °C

0.60 °C

0.32 °C

0.36 °C

0.53 °C

0.36 °C

0.32 °C

0.46 °C

0.19 °C

0.12 °C

0.12 °C

0.16 °C

0.15 °C

0.14 °C

0.37 °C

0.15 °C

0.11 °C

0.36 °C

0.32 °C

0.46 °C

1.97 °C

1.02 °C

0.60 °C

0.55 °C

0.54 °C

0.63 °C

0.91 °C

0.44 °C

0.49 °C

0.69 °C

0.36 °C

0.33 °C

0.46 °C

0.99 °C

0.62 °C

0.48 °C

0.64 °C

0.51 °C

0.41 °C

1.48 °C

0.63 °C

0.40 °C

0.36 °C

0.33 °C

0.46 °C

Thermocouple Measurement Characteristics

Temperature Display Resolution

Range

Slow

Sample Rate

-270 °C to 2315 °C 0.01 °C 0.1 °C

Digital I/O

Absolute Voltage Range ......................................... -4 V to 30 V

Input Minimum Logic High ...................................... 2.0 V

Input Maximum Logic Low ...................................... 0.7 V

Output Type ............................................................ open drain active low

Output Logic Low (<1 mA) ...................................... 0 V to 0.7 V

Maximum Sink Current ........................................... 50 mA

Output Resistance .................................................. 47 Ω

Totalizer

Absolute Voltage Range ......................................... -4 V to 30 V

Minimum Logic High ............................................... 2.0 V

Maximum Logic Low ............................................... 0.7 V

Minimum Pulse Width ............................................. 50 μs

Maximum Frequency .............................................. 10 kHz

Debounce Time ....................................................... 1.7 ms

Maximum Count ...................................................... 1048575 (20 bits)

Medium/Fast
Sample Rate

14

Trigger

Absolute Voltage Range ......................................... -4 V to 30 V

Minimum Logic High ............................................... 2.0 V

HYDRA Series III Data Acquisition Unit

2638A-100 Universal Input Module

Maximum Logic Low ............................................... 0.7 V

Minimum Pulse Width ............................................. 50 μs

Maximum Latency ................................................... 100 ms

Alarm Output

Absolute Voltage Range ......................................... -4 V to 30 V

Output Type ............................................................ open drain active low

Output Logic Low (<1 mA) ...................................... 0 V to 0.7 V

Maximum Sink Current ........................................... 50 mA

Output Resistance ................................................. 47 Ω

2638A-100 Universal Input Module

General

Measurement .......................................................... IEC 61010-2-030: CAT II 150 V, on any range. 250 V Max. (see safety

Offset Voltage ......................................................... <2 μV

3-Wire Internal Resistance Mismatch ..................... <50 mΩ

Basic CJC Accuracy ............................................... 0.6 °C

notice in this manual under input protection)

15

2638A

Calibration Manual

General Maintenance

If the Product Does Not Turn On

Clean the Product

This section supplies information on how to clean the Product, reset the memory,
and replace the fuse in the rear of the Product.

To help solve problems encountered when turning on the Product:

1. Verify that the power switch is in the “On” position.

2. Make sure that the mains power cord is firmly plugged into the power module
on the rear of the Product.

3. Make sure the power source that the Product is plugged into is energized.

4. Verify that the line power fuse is good. See “Replace the Line Power Fuse”.

If these steps do not solve the problem, then contact Fluke. See the “Contact
Fluke”.

To clean the Product, wipe the instrument with a cloth that is lightly dampened
with water or mild detergent. Do not use aromatic hydrocarbons, chlorinated
solvents, or methanol based fluids.

To prevent possible damage to the Product, do not use
solvents or abrasive cleansers.

For safe operation and maintenance of the product:

• Have an approved technician repair the Product.

• Do not allow water to get inside the Product.

Replace the Line Power Fuse

The Product has a fuse that protects from overcurrent. Each voltage selection
requires a specific fuse. See Table 2 for the correct fuse for each of the four line­voltage selections. This fuse is located on the rear panel.

To prevent possible electrical shock, fire, or personal injury,
use only specified replacement parts.

Voltage Selector Fuse Fluke Part Number

100 V 0.25 A, 250 V (slow blow) 166306

120 V 0.25 A, 250 V (slow blow) 166306

WCaution

WCaution

XWWarning

Table 2. Fuses

16

220 V 0.160 A, 250 V (slow blow) 4394437

240 V 0.160 A, 250 V (slow blow) 4394437

HYDRA Series III Data Acquisition Unit

General Maintenance

To replace the fuses, see Figure 1:

1. Remove any high-capacity modules or test leads from the Product where
hazardous voltage may be present.

2. Disconnect the mains-power cord from the power-entry module.

3. Insert a small, flat screwdriver blade into the narrow recess to the left of the
fuse holder and pry to the right until the holder pops out. The Product is
shipped with a replacement fuse of the same rating as the fuse installed in
the fuse block.

4. Replace the fuse with the replacements as listed in Table 2.

5. Slide the fuse holder back into the Product until it locks into place.

1 2

Battery Replacement

The battery in the Product is used for Product memory (menu settings, readings,
or other functions).

To replace the battery:

1. Disassemble the Product as described in the Disassembly section.

2. Remove the battery (see Figure 9) and replace with one rated appropriately
for the selected voltage button battery.

3. Reassemble the Product.

Figure 1. Fuse Replacement

hcn027.eps

17

2638A

Calibration Manual

Memory and Factory Reset

The Product has two memory reset functions to remove data from the memory
and reset the Product:

• Clear all Files

• Factory Reset

See Table 3 for a comparison of these functions.

Note

All memory reset functions require the Admin password.

Table 3. Memory Clear Functions

Task Clear All Files Factory Reset

Deletes Test Setup files, DMM Data files, and Scan
Data files from the internal memory.

Clears the configuration of the Channel Setup, Test
Setup, and Instrument Setup

[1] Does not remove data from the USB drive.
[2] Does not reset the MAC address, the serial number, calibration, clock time, or the Admin or User passwords.

[1]

[2]

•

•

To clear all files:

1. Push .

2. Push  twice.

3. Enter the Admin password.

4. Push .

5. Push  to confirm.

To reset the Product to factory settings:

1. Push .

2. Push .

3. Enter the Admin password, then push .

18

HYDRA Series III Data Acquisition Unit

Firmware Update

Firmware Update

For Products with a firmware version 1.03 or higher, firmware may be updated by
the product administrator with the front-panel USB port. New firmware versions
are available from the Fluke Calibration web page for the Product under the
Knowledge and Information tab.

For Products that have firmware versions below 1.03, contact Fluke Calibration
Service to schedule a firmware update as these versions do not support the USB
firmware update process.

Update instructions for Products that use version 1.03 and above:

WCaution

• Do not cycle the power or remove the USB device while the

firmware update is in process. These actions will cause an
instrument failure during the update process and require a
return to a Fluke Service center to correct.

• The Product automatically re-boots when the update

process is complete. Updates can take several minutes to
complete and the display screen will not illuminate until the
re-boot.

Note

Fluke Calibration recommends that you move all internal data files
and setup files from the Product to a USB device before the update
of the firmware.

Before the update process starts, verify that the current firmware is version 1.03
or above by viewing Firmware under . If your firmware version is below

1.03, do not continue the update process. You must return the Product to Fluke

Calibration Service for the firmware update.

Firmware update steps:

1. Download and extract the firmware update files (AuxInfo.txt and mtv.flt) to
your computer from the Fluke Calibration website.

2. Create a new folder firmware on a USB flash drive (1 GB or greater), and
then copy these files into this folder. To prevent file corruption, use the
Windows utility to safely eject your USB flash drive from your computer.

3. Plug the USB flash drive into the Product and wait for the red light on the
USB port to illuminate and show that the drive is recognized.

Note

Some USB flash drives may not be recognized by the Product. Test
the USB flash drive prior to starting this update process to ensure it
is recognized.

4. Push  to enter the Setup menu.

5. Push the Up/Down arrow button to select Firmware then push  to enter
the firmware menu.

6. Push  and enter the administrator password and then push  to start
the update process.

7. WAIT until the Product automatically re-boots. There will be no screen display
for several minutes during this time. Do not cycle the power or remove the
USB device while the firmware update is in process.

19

2638A

Calibration Manual

Required Equipment

Function Instrument Type Model Comments

Volts DC

8. After the automatic re-boot, push  to verify that the update was
successful. Verify the firmware version that you have installed is displayed on
the screen.

Table 4 lists the equipment required for performance tests and calibration
adjustment of the Product.

Table 4. Required Test Equipment

Standard Fluke 5720A

8½ digit meter Fluke 8508A

4-wire short

Alternate standard

Standard Fluke 5720A

[1]

Fluke low thermal 4-wire
short or equivalent

Fluke 5522A

Used to characterized the
5522A

Fluke PN 2653346

Must be characterized with
8508A

Volts ac

Frequency

Ohms

8½ digit meter Fluke 8508A

4-wire short

Alternate standard

Standard Fluke 5522A

Alternate standard Function generator

Standard Fluke 5720A

4-wire short

Alternate standard

[1]

Fluke low thermal 4-wire
short or equivalent

Fluke 5522A

Fluke low thermal 4-wire
short or equivalent

The standard resistors
which have equivalent
spec with Fluke 5720A.

Used to characterized the
5522A

Fluke PN 2653346

Must be characterized with
8508A

Specifications include

0.075 % frequency
accuracy from 20 Hz to
40 Hz and 0.0025 %
accuracy for frequencies
up to 1 MHz

Fluke PN 2653346

20

HYDRA Series III Data Acquisition Unit

Required Equipment

Table 4. Required Test Equipment (cont.)

Function Instrument Type Model Comments

PRT

Thermistor

Current DC

Current ac

Fluke 5522A
(for 1 kΩ value)

Standard

Standard resistors of
25 Ω, 100 Ω, 200 Ω, and
400 Ω

4-wire short

Fluke low thermal 4-wire
short or equivalent

The standard resistors

Alternate standard

which have equivalent
specification.

Standard Fluke 5522A

8½ digit meter Fluke 8508A

4-wire short

Alternate standard

[1]

Fluke low thermal 4-wire
short or equivalent

Fluke 5720A

Standard Fluke 5522A

8½ digit meter Fluke 8508A

Alternate standard

[1]

Fluke 5720A

Fluke 5522A

Standard

Fluke 5720A (for 10 μA
adjustment)

8½ digit meter Fluke 8508A

Resistance accuracy
specification (k = 2) should
be or better than:

40 ppm (for 25 Ω)
20 ppm (for 100 Ω, 200 Ω

and 400 Ω)

Fluke PN 2653346

Must be characterized with
8508A

Used to characterized the
5522A

Fluke PN 2653346

Must be characterized with
8508A

Used to characterized the
5522A

Fluke 5522A must be
characterized with 8508A

Used to characterized the
5522A

Alternate standard Fluke 5720A

Metrology Drywell

Reference thermistor
probe

Fluke 9171 with insert
block

Fluke 5610-9

Accuracy 0.013 °C or
better at 25 °C

2638A-100
Module

Reference
thermometer

E-type
thermocouples

Fluke 1586A Only for CJC verification

Must be calibrated.

Omega TT-E-24-SLE

Accuracy 0.026 °C or
better at 25 °C

To reduce the possibility of inducing errors with ac signals picked up by the test

Cables

leads, use short, shielded twisted-pair PTFE-insulated test cables between the test
equipment and the Meter. Fluke makes a 2 foot (PN 738716) and 4 foot (PN

738724) PTFE insulated test cable for this purpose

[1] Other alternate standards beside those listed can be used as long as they provide sufficient traceable [Test

uncertaintity Ratios (TURs)] at each calibration and verification point.

21

2638A

Calibration Manual

Test Considerations

For optimum performance, all test procedures should comply with these
recommendations:

• Assure the calibration ambient temperature (T
and 28 °C. Ideally, the calibration should be done at 23 °C ±2 °C.

• Assure ambient relative humidity is <80%.

• Allow a 60-minute warm-up period.

• Use shielded twisted-pair PTFE-insulated cables to reduce settling and noise

errors.

• Keep all input cables as short as possible.

• Ensure that the calibration standards and test procedures used do not

introduce additional errors.

Ideally, the standards used to verify and adjust the Product should
be four times more accurate than each full-scale error specification
of the Product.

• User the Fluke low-thermal 4-Wire short for all voltages and Ohm shorts. See
Table 4 for Fluke part number.

Performance Tests

This section provides performance tests to verify that the Product operates within
published specifications as well as a complete calibration procedure. The
performance test and, if necessary, the calibration adjustment procedure can be
done both periodically and after service or repair.

Note

) is stable and between 18 °C

cal

The performance tests can be used as an acceptance test upon receipt of the
Product. Use the 90-day specifications when an acceptance test is done after the
Product is calibrated.

Fluke provides these performance tests to ensure that the Product is in proper
operating condition. If the Product fails any of the performance tests, calibration
adjustment and/or repair are needed. The performance test works best if done in
the sequence shown in Table 5.

Each of the measurements listed in the following tests assumes the Product is
being tested after a one-hour warm-up in an environment with an ambient
temperature of 18 °C to 28 °C and a relative humidity of <80 %.

Note

All instrument settings for verification use power up conditions
except as noted by the verification step.

22

HYDRA Series III Data Acquisition Unit

Performance Tests

Front Panel Test

To test the keypad and LEDs on the front panel:

1. Push Instrument Setup.

2. Push and hold  for 3 seconds to enter keypad diagnostic.

3. Push every key. The key name should be shown correctly on the screen.

4. Push , , ,  and again, to check the LED.

5. Push  to exit the keypad diagnostic program.

DC Volts Verification

Connect the Product to the test equipment as shown in Figure 2 and apply the
voltages listed in Table 5.

Note

For the 0 V tests, use the 4-wire short to short the Hi/Lo and Sense
inputs.

5522A Calibrator

CALIBRATOR

5520A

2638A HYDRA Series

X

UUT

NC

A.

Figure 2. DC Voltage Test Connections

EX SNS

: OFF

EX GRD

: OFF

5720A Calibrator

OUTPUT

V A

HI

LO

HI

AUX

CURRENT

NORMAL AUX

V, , ,

RTD

A, -SENSE,

HI

FUSED

LO

GUARD

20V PK MAX

SENSE

GUARD GROUND

V

WIDEBAND

HI

LO

TC

AUX V

20A

20V PK MAX

SCOPE

OUT

TRIG

hcn105.eps

23

2638A

Calibration Manual

Table 5. DC Volts Verification Steps

Nominal

Input(V)

Range

90-Day Test Limits 1-Year Test Limits

High Low High Low

0 0.1 3.5 μV -3.5 μV 3.5 μV -3.5 μV

[1]

0.04

0.1 40.0045 mV 39.9955 mV 40.005 mV 39.995 mV

[1]

0.1

0.1 100.006 mV 99.994 mV 100.0072 mV 99.9928 mV

[1]

-0.04

0.1 -39.9955 mV -40.0045 mV -39.995 mV -40.005 mV

[1]

-0.1

0.1 -99.994 mV -100.006 mV -99.9928 mV -100.0072 mV

0 1 7.0 μV -7.0 μV 7.0 μV -7.0 μV

[1]

1

1 1.000025 V 0.999975 V 1.000032 V 0.999968 V

[1]

-1

1 -0.999975 V -1.000025 V -0.999968 V -1.000032 V

0 10 50.0 μV -50.0 μV 50.0 μV -50.0 μV

[1]

10

10 10.00023 V 9.99977 V 10.00029 V 9.99971 V

[1]

-10

10 -9.99977 V -10.00023 V -9.99971 V -10.00029 V

0 100 600.0 μV -600.0 μV 600.0 μV -600.0 μV

[1]

100

100 100.0033 V 99.9967 V 100.0044 V 99.9956 V

[1]

-100

100 -99.9967 V -100.0033 V -99.9956 V -100.0044 V

0 300 6.0 mV -6.0 mV 6.0 mV -6.0 mV

[1]

300

300 300.0153 V 299.9847 V 300.0183 V 299.9817 V

[1]

-300

300 -299.9847 V -300.0153 V -299.9817 V -300.0183 V

[1] 5522A must be used with 8508A to obtain suitable test uncertainty ratio.

24

HYDRA Series III Data Acquisition Unit

Performance Tests

Volts AC and Frequency Verification

Connect the Product to the test equipment as shown in Figure 3 and apply the
voltages listed in Table 6 and Table 7.

5522A Calibrator

CALIBRATOR

5520A

2638A HYDRA Series

UUT

X

EX SNS

: OFF

A.

NC

EX GRD

: OFF

HI

LO

HI

Figure 3. AC Volts Verification Connections

NORMAL AUX

V, , ,

20V PK MAX

5720A Calibrator

OUTPUT

CURRENT

V A

AUX

SENSE

GUARD GROUND

FUSED

V

RTD

LO

GUARD

HI

LO

A, -SENSE,

HI

TC

WIDEBAND

AUX V

20A

20V PK MAX

SCOPE

OUT

TRIG

hcn105.eps

25

2638A

Calibration Manual

Table 6. AC Volts Verification Steps

Nominal Input

90-Day Test Limits 1-Year Test Limits

Range

Ampl. Freq. High Low High Low

100.0 mV 20 Hz 0.1 100.16 mV 99.84 mV 100.16 mV 99.84 mV

100.0 mV 20 kHz 0.1 100.16 mV 99.84 mV 100.16 mV 99.84 mV

100.0 mV 50 kHz 0.1 100.27 mV 99.73 mV 100.27 mV 99.73 mV

100.0 mV 100 kHz 0.1 100.68 mV 99.32 mV 100.68 mV 99.32 mV

1 V 20 Hz 1 1.0016 V 0.9984 V 1.0016 V 0.9984 V

1 V 20 kHz 1 1.0016 V 0.9984 V 1.0016 V 0.9984 V

1 V 50 kHz 1 1.0027 V 0.9973 V 1.0027 V 0.9973 V

1 V 100 kHz 1 1.0068 V 0.9932 V 1.0068 V 0.9932 V

10 V 20 Hz 10 10.016 V 9.984 V 10.016 V 9.984 V

10 V 20 kHz 10 10.016 V 9.984 V 10.016 V 9.984 V

10 V 50 kHz 10 10.027 V 9.973 V 10.027 V 9.973 V

10 V 100 kHz 10 10.068 V 9.932 V 10.068 V 9.973 V

30 V 20 Hz 100 30.083 V 29.917 V 30.083 V 29.917 V

100 V 20 kHz 100 100.16 V 99.84 V 100.16 V 99.84 V

100 V 50 kHz 100 100.27 V 99.73 V 100.27 V 99.73 V

[1]

100 V

100 kHz 100 100.68 V 99.32 V 100.68 V 99.32 V

30 V 20 Hz 300 30.183 V 29.817 V 30.183 V 29.817 V

300 V 20 kHz 300 300.48 V 299.52 V 300.48 V 299.52 V

300 V 50 kHz 300 300.81 V 299.19 V 300.81 V 299.19 V

300 V 100 kHz 300 302.61 V 297.39 V 302.61 V 297.39 V

[1] 5522A must be used with 8508A to obtain suitable test uncertainty ratio.

Table 7. AC Volts Frequency Verification Steps

Nominal Input 90-day Test Limits 1-year Test Limits

Ampl. Frequency High Low High Low

1 V 20 Hz 20.006 Hz 19.994 Hz 20.006 Hz 19.994 Hz

1 V 40 Hz 40.012 Hz 39.988 Hz 40.012 Hz 39.988 Hz

100 mV 300 kHz 300.03 kHz 299.97 kHz 300.03 kHz 299.97 kHz

100 mV 1 MHz 1.0001 MHz 999.9 kHz 1.0001 MHz 999.9 kHz

26

HYDRA Series III Data Acquisition Unit

Performance Tests

4-Wire Ohms Verification

Connect the Product to the test equipment as shown in Figure 4 and apply the
resistance listed in Table 8.

Note

Ω

For the 0

tests, use the 4-wire short to short the Hi/Lo and Sense

inputs.

UUT

NC

NC

5720A Calibrator

SENSE

V

GUARD

WIDEBAND

HI

LO

GROUND

HI

LO

HI

AUX

CURRENT

Figure 4. 4-Wire Ohms Test Equipment Setup

Table 8. 4-Wire Ohms Verification Steps

Nominal

Input

Range

90-Day Test Limits 1-Year Test Limits

High Low High Low

0 Ω 100 0.004 Ω -0.004 Ω 0.004 Ω -0.004 Ω

100 Ω 100 100.012 Ω 99.988 Ω 100.014 Ω 99.986 Ω

0 Ω 1 k 0.00001 kΩ -0.00001 kΩ 0.00001 kΩ -0.00001 kΩ

hcn305.eps

1 k Ω 1 k 1.00009 kΩ 0.99991 kΩ 1.00011 kΩ 0.99989 kΩ

0 Ω 10 k 0.0001 kΩ -0.0001 kΩ 0.0001 kΩ -0.0001 kΩ

10 k Ω 10 k 10.0009 kΩ 9.9991 kΩ 10.0011 kΩ 9.9989 kΩ

0 Ω 100 k 0.001 kΩ -0.001 kΩ 0.001 kΩ -0.001 kΩ

100 k Ω 100 k 100.009 kΩ 99.991 kΩ 100.011 kΩ 99.989 kΩ

0 Ω 1 M 0.00001 MΩ -0.00001 MΩ 0.00001 MΩ -0.00001 MΩ

1 M Ω 1 M 1.00009 MΩ 0.99991 MΩ 1.00011 MΩ 0.99989 MΩ

0 Ω 10 M 0.0001 MΩ -0.0001 MΩ 0.0001 MΩ -0.0001 MΩ

10 M Ω 10 M 10.0021 MΩ 9.9979 MΩ 10.0041 kΩ 9.9959 MΩ

[1]

0 Ω

100 M 0.01 MΩ -0.01 MΩ 0.01 MΩ -0.01 MΩ

100 M Ω

[1] 2-Wire

[1]

100 M 100.81 MΩ 99.19 MΩ 100.81 MΩ 99.19 MΩ

27

2638A

Calibration Manual

PRT Verification Steps

Connect the Product as in Figure 5 for the 1 kΩ value listed in Table 9. For all
other values in the table, use standard resistors. Configure the Ch001 as 4-wire
PRT function with resistance display.

UUT

NC

NC

Figure 5. PRT Verification Connection

Configure Resistance Display

After configuring the channel Ch001 to 4-wire PRT function, send the following
command through the remote interface to configure the resistance display:

TEMP:FPRT:CALC:RES ON,(@1)

Table 9. PRT Verification Steps

Nominal

Input

Range

1 ke

5522A Calibrator

hcn312.eps

1-Year Test Limits

High Low

0 Ω 100 0.005 Ω -0.005 Ω

25 Ω 100 25.0075 Ω 24.9925 Ω

100 Ω 100 100.015 Ω 99.985 Ω

1k Ω 1 k 1.0002 kΩ 0.9998 kΩ

28

HYDRA Series III Data Acquisition Unit

Performance Tests

Thermistor Verification Steps

Connect the Product to the test equipment as shown in Figure 6 and apply the
resistance listed in Table 10. Configure Ch001 as a 4-wire thermistor function
with resistance display.

UUT

NC

NC

Figure 6. Thermistor Test Equipment Setup

Configure Resistance Display

After configuring the channel Ch001 to 4-wire thermistor function, send this
command through the remote interface to configure the resistance display. Apply
the values in Table 10:

TEMP:FTH:CALC:RES ON, (@1)

Table 10. Thermistor Verification Steps

Nominal

Input

Range

5522A Calibrator

hcn304.eps

1-Year Test Limits

High Low

0 Ω 2.2 k 0.5 Ω -0.5 Ω

2 kΩ

90 kΩ 98 k 90010 Ω 89990 Ω

900 kΩ 1 M 900370 Ω 899630 Ω

2.2 k 2000.7 Ω 1999.3 Ω

29

2638A

Calibration Manual

DC Current Verification

Connect the Product to the test equipment as shown in Figure 7 and apply the
resistance listed in Table 11.

Note

When the 5720A/5522A is used as source, connect Hi (source) to Lo
(Product) and Lo (source) to mA (Product). For the 0 A tests, open
Lo inputs.

5522A Calibrator

CALIBR ATOR

5520A

2638A HYDRA Series

UUT

X

EX SNS

: OFF

A.

NC

EX GRD

: OFF

Figure 7. mA DC Current Equipment Setup

HI

LO

HI

CURRENT

OUTPUT

V A

AUX

NORMAL AU X

V, , ,

FUSED

20V PK MAX

RTD

GUAR D

A, -SENSE,

HI

LO

AUX V

20A

20V PK MAX

TC

5720A Calibrator

SENSE

V

WIDEBAND

HI

LO

GUARD GROUND

SCOPE

OUT

TRIG

hcn308.eps

30

HYDRA Series III Data Acquisition Unit

Performance Tests

Table 11. DC Current Verification Steps

Nominal

Input

(mA)

Range

90-Day Test Limits 1-Year Test Limits

High Low High Low

0 0.1 3.5 nA -3.5 nA 3.5 nA -3.5 nA

[1]

0.1

0.1 100.0185 μA 99.9815 μA 100.0185 μA 99.9815 μA

[1]

-0.1

0.1 -99.9815 μA -100.0185 μA -99.9815 μA -100.0185 μA

0 1 11.0 nA -11.0 nA 11.0 nA -11.0 nA

[1]

1

1 1.000161 mA 0.999839 mA 1.000161 mA 0.999839 mA

[1]

-1

1 -0.999839 mA -1.000161 mA -0.999839 mA -1.000161 mA

0 10 0.35 μA -0.35 μA 0.35 μA -0.35 μA

[1]

10

10 10.00185 mA 9.99815 mA 10.00185 mA 9.99815 mA

[1]

-10

10 -9.99815 mA -10.00185 mA -9.99815 mA -10.00185 mA

0 100 3.5 μA -3.5 μA 3.5 μA -3.5 μA

[1]

100

100 100.0185 mA 99.9815 mA 100.0185 mA 99.9815 mA

[1]

-100

100 -99.9815 mA -100.0185 mA -99.9815 mA -100.0185 mA

[1] 5720A or 5522A must be used with 8508A to obtain suitable test uncertainty ratio.

31

2638A

Calibration Manual

AC Current Verification Steps

Connect the Meter to the test equipment as shown in Figure 8 and, depending on
which meter you are calibrating, apply the resistance listed in Table 12.

Note

When use 5720A/5522A as source, connect Hi (source) to Lo
(meter) and Lo (source) to mA (meter). For the zero (0) A tests, open
Lo inputs.

5522A Calibrator

CALIBR ATOR

5520A

2638A HYDRA Series

UUT

X

EX SNS

: OFF

A.

NC

EX GRD

: OFF

Figure 8. mA AC Current Equipment Setup

HI

LO

HI

CURRENT

OUTPUT

V A

AUX

NORMAL AU X

V, , ,

20V PK MAX

RTD

GUAR D

A, -SENSE,

HI

LO

AUX V

FUSED

20A

20V PK MAX

TC

5720A Calibrator

SENSE

V

WIDEBAND

HI

LO

GUARD GROUND

SCOPE

OUT

TRIG

hcn311.eps

32

HYDRA Series III Data Acquisition Unit

Performance Tests

Table 12. AC Current Verification Steps

Nominal Input

Ampl. Frequency High Low High Low

100.0 μA

100.0 μA

1.0 mA

1.0 mA

10.0 mA

10.0 mA

100.0 mA

100.0 mA

[1] 5522A must be used with 8508A to obtain suitable test uncertainty ratio.

[1]

20 Hz 0.1 100.31 µA 99.69 µA 100.36 µA 99.64 µA

[1]

2 kHz 0.1 100.31 µA 99.69 µA 100.36 µA 99.64 µA

[1]

20 Hz 1 1.0031 mA 0.9969 mA 1.0036 mA 0.9964 mA

[1]

2 kHz 1 1.0031 mA 0.9969 mA 1.0036 mA 0.9964 mA

[1]

20 Hz 10 10.031 mA 9.969 mA 10.036 mA 9.964 mA

[1]

2 kHz 10 10.031 mA 9.969 mA 10.036 mA 9.964 mA

[1]

20 Hz 100 100.31 mA 99.69 mA 100.36 mA 99.64 mA

[1]

2 kHz 100 100.31 mA 99.69 mA 100.36 mA 99.64 mA

Range

90-day Test Limits 1-year Test Limits

2638A-100 Module Verification

1. Connect the calibrated E-type thermocouples to channel 10 on the Product.

2. Insert the thermocouples into a drywell calibrator which is set and stabilized
at 25 °C.

3. Configure the channels of the Product for an E-thermocouple.

4. Insert the reference thermistor probe into the drywell to measure the actual
temperature.

5. Use the reference thermometer with the reference thermistor probe and the
thermocouples on the Product to measure the drywell temperature until all
readings are stable.

6. Compare the thermocouple readings and reference thermometer reading.
The difference should be <0.6 °C.

33

2638A

Calibration Manual

Calibration Adjustment

Calibration adjustment should be done at the specified interval, or whenever a
verification test indicates that a Product function is out of tolerance. Product
accuracy stays within specifications only if the adjustment procedure is done at
regular intervals. A one-year interval is adequate for most applications. Product
accuracy specifications are not valid beyond the one-year interval.

Adjustments are accessed through both the remote interface and front panel with
a series of adjustment steps. The remote program directs the test equipment to
apply a series of shorts, opens, voltages, currents, and resistances to the
Product. At each step, the Product internally makes the necessary adjustment to
bring the Product into specification. No internal mechanical adjustments are
necessary.

With an automated, computer-controlled procedure, the calibration and
verification procedures can be done in under an hour. A simple adjustment
program is listed in the Sample Adjustment Program section.

Adjustments are password protected to prevent accidental or unauthorized
adjustments. The admin password must be entered through the front panel or
remote interface.

Unlock the Product

To unlock the Product for adjustments from the front panel:

1. Push Instrument Setup.
Push Calibrate.

2.

3. Use the numeric keypad to enter the 4-digit admin password.

4.

Push OK to

The Product is shipped from the factory with the password set to 2638.

Unlock the Product with a Remote Interface

To unlock the Product with a remote interface, send the command:

CAL:SEC:STAT OFF,“2638”

To relock the Product, send the command:

CAL:SEC:STAT ON

enter the password and continue the adjustments procedure.

34

HYDRA Series III Data Acquisition Unit

Calibration Adjustment

Reset the Admin Password

If the admin password is lost or forgotten, the password can be reset to 2638 with
these steps:

Note

Before doing these steps, try to use the factory default password:

2638.

1. Do the general disassembly steps in the “Disassembly” section.

2. Connect a jumper across J8, as shown in Figure 9.

3. Reconnect the mains power cable between the Product and a power outlet.

4. Turn the Product on.

5. When the Product is started, the password will automatically be reset to

2638.

6. Turn the Product off and disconnect the mains power cable.

7. Remove the jumper connected in step 2.

8. Reassemble the Product by doing the reverse procedure in “Disassembly”.

Display

Cable

InGuard

Shield

Short J8, then turn on the power.
After the instrument is successfully
started, the admin password is
reset to 2638.

Battery

J8

RST PSW

A6

PCB

Assembly

Fan

Figure 9. Password Reset Jumper

hcn103.eps

35

2638A

Calibration Manual

Disassembly

XWWarning

To prevent possible electrical shock or personal injury,
disconnect the mains power cord before you remove the
Product covers.

Only disassemble the Product to reset the password or replace the battery. See
Figure 10.

A 2# Phillips screwdriver and small crescent wrench are required to disassemble
the Product.

1. Remove all high-capacity modules and test leads from the Product.

2. Turn off the mains power at the rear of the Product and remove the mains
power cord. The front panel power key only puts the Product into a power­save mode and does not remove mains power.

3. Remove the boots  by pulling from a corner and stretching the bumpers off
the Product.

4. Remove the bail  by rotating the handle upright to a 90 ° angle from the top
of the Product and pulling  the bail out from the sides.

5. Remove the top cover by removing the two screws on the sides of the
chassis, and slide the cover towards the back of the Product .

36

HYDRA Series III Data Acquisition Unit

Calibration Adjustment

1

Boot Removal

3

To Remove, Pull End From Unit

2

4

6

5

Battery

hcn309.eps

Figure 10. Disassembly

37

2638A

Calibration Manual

Change the Calibration Date Remotely

“Mainframe” Adjustment Process

The calibration date is automatically updated when the “CALibrate:STORe”
command is sent.

Table 13 lists:

• Steps

• Description of the adjustment

• Measurement adjustment type (open, zero, or gain adjustment)

• Product value or range that is to be adjusted

• Amplitude of the adjustment signal

• The frequency of the adjustment signal (if necessary)

Table 13. Adjustment Steps

Step

MAIN

A2D open ADC self-calibration Y

ACV

AC100MV 0.1

AC_100MV_1 100.0 mV, 1 kHz N

AC_50MV_1 50.0 mV, 1 kHz N

AC_25MV_1 25.0 mV, 1 kHz N

AC_5MV_1 5.0 mV, 1 kHz N

AC_0V_1 0.0 V N

AC1V 1.0

AC_1V_2 1.0 V, 1 kHz N

AC_0_5V_2 0.5 V, 1 kHz N

AC_0_25V_2 0.25 V, 1 kHz N

Value

Range

Input Signal Description

Start calibration of
ac 100 mV range

Start calibration of
ac 1 V range

Y

Y

Entry
Point

38

AC_0_05V_2 0.05 V, 1 kHz N

AC_0V_2 0.0 V N

AC_1V_LF 1 V, 20 Hz

AC10V 10.0

AC_10V_3 1.0 V, 1 kHz N

AC_5V_3 5.0 V, 1 kHz N

AC LF
compensation

Start calibration of
ac 10 V range

N

Y

HYDRA Series III Data Acquisition Unit

Calibration Adjustment

Table 13. Adjustment Steps (cont.)

Step

AC_2_5V_3 2.5 V, 1 kHz N

AC_0_5V_3 0.5 V, 1 kHz N

AC_0V_3 0.0 V N

AC100V 100.0

AC_100V_4 100.0 V, 1 kHz N

AC_50V_4 50.0 V , 1 kHz N

AC_25V_4 25.0 V, 1 kHz N

AC_5V_4 5.0 V, 1 kHz N

AC_0V_4 0.0 V N

AC300V 300.0

AC_300V_5 300.0 V, 1 kHz N

AC_200V_5 200.0 V, 1 kHz N

AC_100V_5 100.0 V, 1 kHz N

Value

Range

Input Signal Description

Start calibration of ac
100 V range

Start calibration of ac
300 V range

Y

Y

Entry
Point

AC_50V_5 50.0 V, 1 kHz N

AC_0V_5 0.0 V N

DCV

DC100MV 0.1

DC_P100MV_1 100.0 mV N

DC_0V_1 0.0 V N

DC_N100MV_1 -100.0 mV N

DC1V 1.0

DC_P1V_2 1.0 V N

DC_0V_2 0.0 V N

DC_N1V_2 -1.0 V N

DC10V 10.0

DC_P10V_3 10.0 V N

DC_0V_3 0.0 V N

Start calibration of dc
100 mV range

Start calibration of dc 1 V
range

Start calibration of dc
10 V range

Y

Y

Y

39

2638A

Calibration Manual

Table 13. Adjustment Steps (cont.)

Step Value Range

DC_N10V_3 -10.0 V N

DC100V 100.0

DC_P100V_4 100.0 V N

DC_0V_4 0.0 V N

DC_N100V_4 -100.0 V N

DC300V 300.0

DC_P300V_5 300.0 V N

DC_0V_5 0.0 V N

DC_N300V_5 -300.0 V N

OHM

R100 100.0

R_100_1 100.0 Ω N

Input

Signal

Start calibration of dc 100 V
range

Start calibration of dc 300 V
range

Start calibration of FRES
100 Ω range

Description

Entry
Point

Y

Y

Y

R_19_1 19.0 Ω N

R_0_1 0.0 Ω N

R1K 1.0E+3

R_1K_2 1.0 kΩ N

R_190_2 190.0 Ω N

R_0_2 0.0 Ω N

R10K 10.0E+3

R_10K_3 10.0 kΩ N

R_1_9K_3 1.9 kΩ N

R_0_3 0.0 Ω N

R100K 100.0E+3

R_100K_4 100.0 kΩ N

R_19K_4 19.0 kΩ N

Start calibration of FRES
1 kΩ range

Start calibration of FRES
10 kΩ range

Start calibration of FRES
100 kΩ range

Y

Y

Y

40

HYDRA Series III Data Acquisition Unit

Calibration Adjustment

Table 13. Adjustment Steps (cont.)

Step Value Range

R_0_4 0.0 Ω N

R1M 1.0E+6

R_1M_5 1.0 MΩ N

R_190K_5 190.0 kΩ N

R_100K_5 100.0 kΩ N

R_0_5 0.0 Ω N

R10M 10.0E+6

R_10M_6 10.0 MΩ N

R_1_9M_6 1.9 MΩ N

R_1_0M_6 1.0 MΩ N

R_0_6 0.0 Ω N

R100M 100.0E+6

Input

Signal

Start calibration of FRES
1 MΩ range

Start calibration of RES
10 MΩ range

Start calibration of RES
100 MΩ range

Description

Entry
Point

Y

Y

Y

R_100M_7 100.0 MΩ N

R_19M_7 19.0 MΩ N

R_0_7 0.0 Ω N

THERM

T2K 2.2E+3

T_1_9K_1 1.9 kΩ N

T_1_0K_1 1.0 kΩ N

T_190_1 190.0 Ω N

T_0_1 0.0 Ω N

T90K 90.0E+3

T_100K_2 100.0 kΩ N

T_19K_2 19.0 kΩ N

T_10K_2 10.0 kΩ N

T_0_2 0.0 Ω N

Start calibration of FTH
2 kΩ range

Start calibration of FTH
90 kΩ range

Y

Y

T1M 90.0E+3

Start calibration of FTH
1 MΩ range

Y

41

2638A

Calibration Manual

Table 13. Adjustment Steps (cont.)

Step Value Range

T_1M_3 1.0 MΩ N

T_190K_3 190.0 kΩ N

T_100K_3 100.0 kΩ N

T_0_3 0.0 Ω N

HZ

HZ1K

HERTZ

ACI

AC100UA 100.0E-6

AC_100UA_1

AC_50UA_1

Input

Signal

1000.0 Hz,
1 V

100.0 μA,
500 Hz

50.0 μA,
500 Hz

Description

Start calibration of
frequency

N

Start calibration of ac
100 μA range

N

N

Entry
Point

Y

Y

AC_25UA_1

AC_10UA_1

AC_0A_1 Open N

AC1MA 1.0E-3

AC_1MA_2

AC_0_5MA_2

AC_0_25MA_2

AC_0_05MA_2

AC_0A_2 Open N

AC10MA 10.0E-3

AC_10MA_3

25.0 μA,
500 Hz

10.0 μA,
500 Hz

1.0 mA,
500 Hz

0.5 mA,
500 Hz

0.25 mA,
500 Hz

0.05 mA,
500 Hz

10.0 mA,
500 Hz

N

N

Start calibration of ac 1 mA
range

N

N

N

N

Start calibration of ac
10 mA range

N

Y

Y

42

HYDRA Series III Data Acquisition Unit

Calibration Adjustment

Table 13. Adjustment Steps (cont.)

Step Value Range Input Signal Description

AC_5MA_3 5.0 mA, 500 Hz N

AC_2_5MA_3 2.5 mA, 500 Hz N

AC_0_5MA_3 0.5 mA, 500 Hz N

AC_0A_3 Open N

AC100MA 100.0E-3

AC_100MA_1

AC_50MA_1 50.0 mA, 500 Hz N

AC_25MA_1 25.0 mA, 500 Hz N

AC_5MA_1 5.0 mA, 500 Hz N

AC_0A_1 Open N

DCI

DC100UA 100.0E-6

100.0 mA,
500 Hz

Start calibration of ac
100 mA range

N

Start calibration of dc
100 μA range

Entry
Point

Y

Y

DC_P100UA_1 100.0 μA N

DC_0A_1 Open N

DC_N100UA_1 -100.0 μA N

DC1MA 1.0E-3

DC_P1_0MA_2 1.0 mA N

DC_0A_2 Open N

DC_N1_0MA_2 -1.0 mA N

DC10MA 10.0E-3

DC_P10MA_3 10.0 mA N

DC_0A_3 Open N

DC_N10MA_3 -10.0 mA N

DC100MA 100.0E-3

DC_P100MA_4 100.0 mA N

DC_0A_4 Open N

Start calibration of dc
1 mA range

Start calibration of dc
10 mA range

Start calibration of dc
100 mA range

Y

Y

Y

DC_N100MA_4 -100.0 mA N

43

2638A

Calibration Manual

Remote Commands for Calibration

Table 14 alphabetically lists the command set for calibration.

Table 14. List of Commands

Remote Command Meaning

CALibrate:ABORt

CALibrate:BACKup

CALibrate:CONSt?

CALibrate:DATE?

CALibrate:INFO?

CALibrate:MOD:DATE
<slot>,<year>,<month>,<day>

CALibrate:NEXT [<reference>] Continue a calibration procedure if it is waiting.

CALibrate:REF? Return nominal value expected for reference entry.

CALibrate:SECure:STATe
<boolean>,<admin_password>

CALibrate:SECTion Skip to next section of calibration procedure.

CALibrate:SKIP Skip to next entry point in calibration procedure.

CALibrate:STARt <procedure>[,<step>] Start a calibration procedure.

Instruct unit to abort calibration procedure after
present step.

Backup to previous entry point in calibration
procedure.

Retrieve the value in use of the given calibration
constant.

Return a CAL date associated with stored
calibration constants.

Return message or instructions associated with
running step.

Set CAL date of module in specified slot.

Instruct unit to enable calibration.

44

CALibrate:STATe? Return state of calibration.

CALibrate:STEP? Return name of step currently running.

CALibrate:STORe Store new calibration constants.

CALibrate:MODule:DATE
<slot>,<year>,<month>,<day>

Set module CAL date.

HYDRA Series III Data Acquisition Unit

Remote Commands for Calibration

Remote Programming Examples

This section gives examples of command sequences for several likely scenarios.

Start a Full Calibration

Table 15 shows an example to run a full calibration.

Table 15. Full Calibration Example

Command Action

CAL:SEC:STAT OFF,”2638” Disable the security for calibration.

CAL:STAR MAIN

CAL:NEXT Continue to show instruction of ACV calibration.

CAL:NEXT

CAL:NEXT

CAL:NEXT 0.1

CAL:NEXT 0.05

CAL:NEXT 0.025

CAL:NEXT 0.005

Start MAIN calibration procedure, and show instruction of MAIN
calibration procedure.

Continue to perform ACV calibration.
After it is completed, show instruction to connect the calibrator to

the instrument for ACV calibration.

Show instruction to ask for 100 mV/1 kHz signal input, and the
reference value.

Continue to perform measurements for this point, after it is
completed, show instruction to ask for 50 mV/1 kHz signal input
and the reference value.

Continue to perform measurements for this point, after it is
completed, show instruction to ask for 25 mV/1 kHz signal input
and the reference value.

Continue to perform measurements for this point, after it is
completed, show instruction to ask for 5 mV/1 kHz signal input
and the reference value.

Continue to perform measurements for this point, after it is
completed, show instruction to ask for 0V signal input and the
reference value.

Continue to perform measurements for this point, after it is
completed, calculate the calibration constants for ac 100 mV

CAL:NEXT 0.0

… …

CAL:STOR Store the calibration constants.

CAL:ABOR Abort the calibration procedure.

range, then show instruction to ask for 1 V/1 kHz signal input and
the reference value (the first calibration point of next ac 1 V
range.

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Calibrate 1 V DC Range only

CAL:SEC:STAT OFF,”2638” Disable the security for calibration.

CAL:STAR MAIN,DC1V

CAL:NEXT 1

CAL:NEXT 0

CAL:NEXT -1

Table 16 shows an example to run a calibration for 1 V dc.

Table 16. 1 V DC Calibration Example

Command Action

Start MAIN calibration procedure, and jump to 1 V dc range
directly, it will show ask for 1 V signal input, and the reference
value.

Continue to perform measurements for this point, after it is
completed, show instruction to ask for 0 V signal input and the
reference value.

Continue to perform measurements for this point, after it is
completed, show instruction to ask for -1 V signal input and the
reference value.

Continue to perform measurements for this point, after it is
completed, calculate the calibration constants for DC 1V range,
then show instruction to ask for 10 V signal input and the
reference value (the first calibration point of next 10 V dc range.

CAL:STOR Store the calibration constants.

CAL:ABOR Abort the calibration procedure.

Write Calibration Date to a Module

Table 17 shows an example to write the calibration date into a module after the
CJC accuracy is validated.

Table 17. Write Calibration Date to a Module Example

Command Action

CAL:SEC:STAT OFF,”2638” Disable the security for calibration.

CAL:MOD:DATE 1,2014,11,1 Write “2014/11/1” as new calibration date into module in slot 1.

46

HYDRA Series III Data Acquisition Unit

Remote Commands for Calibration

Command References

CALibrate:ABORt

Description: Instruct unit to abort calibration procedure after present

step.
Example: CAL:ABOR
Related Commands:

CALibrate:STATe?

CALibrate:BACKup

Description: Backup to previous entry point in calibration procedure.
Example: CAL:BACK
Related Commands:

CALibrate:SKIP
CALibrate:SECTion

CALibrate:CONSt? “<cco_name>”

Description: Retrieves the value in use of the given calibration constant.

Example: CAL:CONS? “DC100MV_A1”
Response: -1.401686110719e-04
Related Commands:
CALibrate:SECure:STATe
CALibrate:STORe

CALibrate:DATE?

Description: Return a CAL date associated with stored calibration

constants.

Example: CAL:DATE?
Response: 2013,11,1
Related Commands:
CALibrate:MODule:DATE?

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Calibration Manual

CALibrate:INFOrmation?

Description: Return message or instructions associated with

running step.

Example: CAL:INFO?
Response: “Connect calibrator to Volt terminals”
Related Commands:
CALibrate:STATe?

CALibrate:STEP?

CALibrate:MODule:DATE <slot>,<year>,<month>,<day>
CALibrate:MODule:DATE? <slot>

Description: Set and query module calibration date.
Example: CAL:MOD:DATE 1,2013,11,1
CAL:MOD:DATE? 1
Response: 2013,11,1
Related Commands:
CALibrate:SECure:STATe

CALibrate:NEXT [<reference>]

Description: Continue a calibration procedure if it is waiting. An

optional parameter reference value (used if it's waiting

for a reference), If the reference value has no unit, the

unit is assumed to be that returned by the CAL_REF?

command.
Example: CAL_NEXT

CAL_NEXT 2.999987
CAL_NEXT 100 mV

Related Commands:

CALibrate:REFerence?
CALibrate:BACKup
CALibrate:SKIP

48

HYDRA Series III Data Acquisition Unit

Remote Commands for Calibration

CALibrate:REFerence?

Description: Return nominal value expected for reference entry.

Example: CAL:REF?
Response: 3.000000e+00
Related Commands:
CALibrate:NEXT

CALibrate:STATe?
CALibrate:INFOrmation?
CALibrate:STEP?

CALibrate:SECure:STATe <boolean>, <admin_password>

Description: Instruct unit to enable calibration.
Example: CAL:SEC:STATE OFF,”1586”
Related Commands:

CALibrate:SECure:STATe?

CALibrate:SECure:STATe?

Description: Query calibration enable state.
Example: CAL:SEC:STAT?
Response: 1
Related Commands:

CALibrate:SECure:STATe

CALibrate:SECTion

Description: Skip to next section of calibration procedure.
Example: CAL:SECT
Related Commands:

CALibrate:BACKup
CALibrate:SKIP

CALibrate:SKIP

Description: Skip to next entry point in calibration procedure.
Example: CAL:SKIP
Related Commands:

CALibrate:BACKup
CALibrate:SECTion

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CALibrate:STARt <procedure>[,<step>]

Description: Start a calibration procedure. As parameter, the name

of procedure should be provided (MAIN is the

procedure for full instrument calibration), an optional

parameter <step> can be provided to start from, if it is

omitted, it starts at the beginning. Before any

calibration procedure can be started, the calibration

secure state should be disabled.
Example: CAL_START MAIN

CAL_START MAIN,DC1V

Related Commands:

CALibrate:SECure:STATe

CALibrate:STATe?

Description: Return state of calibration.

Example: CAL:STAT?

Response: RUN - running a calibration step

REF - waiting for a CAL_NEXT with reference

(measurement) value
INS - instruction available, waiting for a CAL_NEXT
NOT - not in a calibration procedure (or at end of one)
Related Commands:
CALibrate:STEP?
CALibrate:REFerence?

CALibrate:INFOrmation?

50

HYDRA Series III Data Acquisition Unit

Remote Commands for Calibration

CALibrate:STEP?

Description: Return name of step currently running.
Example: CAL:STEP?
Response: DC1V
Related Commands:

CALibrate:STATe?
CALibrate:REFerence?
CALibrate:INFOrmation?

CALibrate:STORe
CALibrate:STORe?

Description: Store new calibration constants or query whether a

cal store is needed.

Example: CAL:STOR

CAL:STOR?

Response: 1 is yes, 0 if no
Related Commands:

CALibrate:SECure:STATe

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Calibration Manual

User-Replaceable Parts and Accessories

Table 18 lists the part numbers of each user-replaceable part or accessory for
the Product, see Figure 11.

Table 18. User-Replaceable Parts and Accessories

Fluke

Item

Part

Number

Qty Description

 4281998 1 FLUKE-1586A-2010, 2638A HANDLE

 4281980 1 FLUKE-1586A-2009, 2638A FRONT PANEL BOOT

 4281971 1 FLUKE-1586A-2008, 2638A REAR PANEL BOOT

 4396173 1 FLUKE 1586A-2586 RELAY CARD

 4374731 1 FLUKE-1586A-2586, 2638A, PROTECTIVE SLOT COVER

 4338362 1 FLUKE-2638A, REAR SLOT FRAME

SCREW,4-40 X 0.375

 4357143 6

IN.,FLAT,PHILLIPS,SS,PASSIVATED,LOCK
PATCH,ROHS COMPLIANT



Not Shown 1588940 1

Not Shown 4410441 1 Transit Case

Not Shown 4121552 1 884X-4GB,USB MEMORY, 4GB

Not Shown 4298499 1 CABLE, USB MALE A TO MALE B, 2M

Not Shown

Not Shown

Not Shown 4394437 1 WFUSE,0.16A,250V,SLOW,0.5 I2T,6X32MM,CERAMIC

Not Shown 166306 1 W Fuse 0.25A, 250V (slow blow)

[1] Quantity of items listed can vary based on kit or model ordered.
[2] Only use exact replacements.

Contact
Fluke

884X­ETH

Variable

[3]

1 FLUKE 1586A-2586 HI-CAPACITY MODULE

BATTERY,PRIMARY,LI­MNO2,3V,560MAH,COIN,CR2450,24X5MM,BULK

1 884X-ETH, ETHERNET INTERFACE CABLE, 1m

1 Test lead set

[3]

[2]

[2]

52

HYDRA Series III Data Acquisition Unit

User-Replaceable Parts and Accessories

1

2

3

4

6

7

8

5

Figure 11. Replaceable Parts

hcn310.eps

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2638A

Calibration Manual

54