Fluke 1504 8.2 Calibration Procedure

8.2 Calibration Procedure

Calibration requires four-wire 10 kΩand 100 kΩresistors of 25 ppm uncer-

tainty and a 0Ωresistor (or short). Forverification, 4 kΩand40kΩresistorsof

25 ppm uncertainty,and a 1 MΩresistor of 75 ppm uncertainty are also re-

quired. The resistorsare connected to the input the same way probes are. The

calibration procedure is as follows:

1. Connect a 0Ωresistor to the input and measure its resistance. Note the

average error in the measurement. Adjust the CAL0 parameter by sub-

tracting the measured error. For example, if the input is exactly 0.0Ωand

readout shows –0.11Ω, the CAL0 parameter should be adjusted by add-

ing 0.11 to it.

2. Connect a 10 kΩresistor to the input and measure its resistance. Note

the average error in the measurement. Adjust the CAL10 parameter by

subtracting the measured error. For example, if the input is exactly

10.000 kΩand the readout shows 10001.9Ω, the CAL100 parameter

should be adjusted by subtracting 1.9 from it.

3. Connect a 100 kΩresistor to the input and measure its resistance. Note

the average error in the measurement. Adjust the CAL100 parameter by

subtracting the measured error. For example, if the input is exactly

100.000 kΩand the readout shows 999991Ω, the CAL400 parameter

should be adjusted by adding 9.0 to it.

4. Verify the accuracy at 0Ω, 4 kΩ, 10 kΩ, 40 kΩ, 100 kΩ, and 1 MΩ. The

accuracy should be within the short-term accuracy limits given in the

specifications.

1504 Thermometer Readout

User’s Guide

36

Contents

Main Rev. 571202 Table of Contents ii 7.3 Remote Commands . . . . . . . . . . . . . . . . . . . . . . . . . 28 8 Calibration Procedure . . . . . . . . . . . . . . . . . . . . . . 35 Page Page 1 Before You Start 1.1 Symbols Used 1.2 Safety Information 1.2.1 Warnings Page 1.2.2 Cautions 1.3 Authorized Service Centers Page Page 2 Introduction 3 Specifications and Environmental Conditions 3.1 Specifications 9 3 Specifications and Environmental Conditions Specifications 3.2 Environmental Conditions 4 Quick Start 4.1 Unpacking 4.2 Power 4.3 Connecting the Probe 4.4 DC Power Option + Page 5 Parts and Controls 5.1 Front Panel Buttons 84.9814 C 5.2 Rear Panel l 6 General Operation 6.1 Selecting Units 6.2 Parameter Menus 6.3 Menu Lockout Page 6.4 Selecting the Probe Characterization 6.4.1 Setting the Probe Characterization Type Pr= thr Pr= rtd 6.4.2 Setting the Characterization Coefficients b0 +4.336079 E -04 6.4.3 Steinhart-Hart Characterization () [] 6.4.4 Callendar-Van Dusen (RTD) Conversion The RTDconversion uses the Callendar-VanDusen equation: [] ()() () 6.4.5 Testing the coefficients 6.5 Filtering Page 7 Digital Communications Interface 7.1 Serial Interface 7.1.1 Setting the Baud Rate 7.1.2 Automatic Transmission of Measurements 7.1.3 Time Stamp and System Clock 7.1.4 Duplex Mode and Linefeed 7.2 GPIB Interface 7.2.1 Setting the Address 7.2.2 Setting the Termination Character 7.2.3 Time Stamp 7.3 Remote Commands 7.3.1 Measurement Commands 29 7 Digital Communications Interface Remote Commands Table 5 Command List , n Page 7.3.2 Probe Characterization Commands 7.3.3 Sample Commands 7.3.4 Communication Commands 7.3.5 Calibration Commands 7.3.6 Other Commands 8 Calibration Procedure 8.1 Accessing the Calibration Parameters 8.2 Calibration Procedure 9 Maintenance 10 Troubleshooting 10.1 CE Comments 10.1.1 EMC Directive 10.1.2 Low Voltage Directive (Safety)