Lakeshore 102 User Manual

User’s Manual

Model 102

Current Source

Lake Shore Cryotronics, Inc.
575 McCorkle Boulevard
Westerville, Ohio 43082-8888 USA

E-Mail Addresses:

[e-mail]
[e-mail]

Internet Addresses:

www.lakeshore.com

Fax: [phone]
Telephone: [phone]

Methods and apparatus disclosed and described herein have been developed solely on company
funds of Lake Shore Cryotronics, Inc. No government or other contractual support or relationship
whatsoever has existed which in any way affects or mitigates proprietary rights of Lake Shore
Cryotronics, Inc. in these developments. Methods and apparatus disclosed herein may be subject
to U.S. Patents existing or applied for. Lake Shore Cryotronics, Inc. reserves the right to add,
improve, modify, or withdraw functions, design modifications, or products at any time without
notice. Lake Shore shall not be liable for errors contained herein or for incidental or consequential
damages in connection with furnishing, performance, or use of this material.

Rev. 1.2 P/N 119-014 9 September 2002

Lake Shore Model 102 User’s Manual

LIMITED WARRANTY

Lake Shore Cryotronics, Inc. (henceforth Lake Shore), the manufacturer, warrants this
product to be free from defects in material and workmanship for a period of 12 months
from the date of shipment. During the warranty period, under authorized return of
instruments or component parts to Lake Shore freight prepaid, the company will
repair, or at its option replace, any part found to be defective in material or
workmanship, without charge to the Owner for parts, service labor, or associated
customary shipping cost. Replacement or repaired parts will be warranted for only the
unexpired portion of the original warranty or 90 days (whichever is greater).

All products are thoroughly tested and calibrated to published specifications prior to
shipment. Calibration Certifications are offered for 12-month periods only. Where such
documentation must be updated, a re-certification service is offered by Lake Shore at
a reasonable cost.

LIMITATION OF WARRANTY

This warranty is limited to Lake Shore products purchased and installed in the United
States, or Internationally through our approved distribution agents. This same
protection will extend to any subsequent owner during the warranty period. It does not
apply to damage resulting from improper or inadequate maintenance, unauthorized
modification or misuse, or operation outside of the environmental specifications. It
does not apply to damage caused by accident, misuse, fire, flood, or acts of God, or
from failure to properly install, operate, or maintain the product in accordance with the
printed instruction provided.

This warranty is in lieu of any other warranties, expressed or implied, including
merchantability or fitness for a particular purpose, which are expressly excluded. The
owner agrees that Lake Shore’s liability with respect to this product shall be set forth in
this warranty, and incidental or consequential damages are expressly excluded.

CERTIFICATION

Lake Shore certifies that this product has been inspected and tested in accordance
with its published specifications and that this product met its published specifications
at the time of shipment. The accuracy and calibration of this product at the time of
shipment are traceable to the United States National Institute of Standards and
Technology (NIST); formerly known as the National Bureau of Standards (NBS), or to
a recognized natural standard.

TRADEM ARK ACKNOWLEDGEMENT

Manufacturers and sellers claim many designations as trademarks to distinguish their
products. Where those designations appear in this manual and Lake Shore was aware
of a trademark claim, the designations appear in initial capital letters with a ™ or
symbol.

®

Apiezon® is a trademark of Biddle Instruments.
CalCurve™, Carbon-Glass™, Cernox™, Duo-Twist™,

High-Temperature Cernox™, Quad-Lead™, Quad-Twist™, Rox™,
SoftCal™, and Thermox™ are trademarks of Lake Shore Cryotronics, Inc.

®

is a trademark of DuPont De Nemours.

Teflon

Copyright © 1993, 1997, 1999, and 2002 by Lake Shore Cryotronics, Inc. All rights
reserved. No portion of this manual may be reproduced, stored in a retrieval system,
or transmitted, in any form or by any means, electronic, mechanical, photocopying,
recording, or otherwise, without the express written permission of Lake Shore.

A

Lake Shore Model 102 User’s Manual

TABLE OF CONTENTS

Chapter/Paragraph Title Page

1 INTRODUCTION.......................................................................... 1-1

1.0 General ...................................................................... 1-1

1.1 Model 102 System Description................................... 1-1

1.2 Handling Liquid Helium and Liquid Nitrogen .............. 1-3

1.2.1 Handling Cryogenic Storage Dewars...................... 1-3

1.2.2 LHe and LN

1.2.3 Recommended First Aid ......................................... 1-4

1.3 Electrostatic Discharge............................................... 1-4

1.3.1 Identifying ESDS Components ............................... 1-5

1.3.2 Handling ESDS Components ................................. 1-5

1.4 Safety Summary......................................................... 1-5

1.5 Safety Symbols .......................................................... 1-6

2 INSTALLATION........................................................................... 2-1

2.0 General ...................................................................... 2-1

2.1 Inspection and Unpacking .......................................... 2-1

2.2 Repackaging For Shipment........................................ 2-1

2.3 Power and Ground Requirements.............................. 2-2

2.4 Sensor Installation Recommendations....................... 2-2

2.4.1 Connecting Leads to the Sensor ............................ 2-3

2.4.2 Sensor Mounting.....................................................2-3

2.4.3 Measurement Errors Due To AC Noise .................. 2-4

Safety Precautions ............................ 1-3

2

3 OPERATION................................................................................ 3-1

3.0 General ...................................................................... 3-1

3.1 Front Panel Features and Functions .......................... 3-1

3.2 Operational Notes ...................................................... 3-2

4 SERVICE ..................................................................................... 4-1

4.0 General ...................................................................... 4-1

4.1 Output Current Programming..................................... 4-1

4.2 Calibration.................................................................. 4-1

4.2.1 Current Calibration Using DC Amp Range ............. 4-2

4.2.2 Current Calibration Using DC Volt Range...............4-3

Table of Contents i

Figure No. Title Page

Lake Shore Model 102 User’s Manual

LIST OF ILLUSTRATIONS

1-1 Typical Cryogenic Storage Dewar ............................................ 1-3

3-1 Model 102 Front Panel ............................................................. 3-2

3-2 Typical Model 102 Application .................................................. 3-2

4-1 Model 102 PCB Layout............................................................. 4-2

LIST OF TABLES

Table No. Title Page

1-1 Model 102 Specifications..........................................................1-2

ii Table of Contents

Lake Shore Model 102 User’s Manual

CHAPTER 1

INTRODUCTION

1.0 GENERAL

Lake Shore Cryotronics designed and manufactured the Model 102
Current Source in the USA. This chapter covers a general description in
Paragraph 1.1, Handling Liquid Helium and Liquid Nitrogen in
Paragraph 1.2, Electrostatic Discharge in Paragraph 1.3, Safety
Summary in Paragraph 1.4, and Safety Symbols in Paragraph 1.5.

We welcome comments on this manual. Although we try to keep it error-free,
some may occur. To report an error, describe it briefly and include the
appropriate paragraph, figure, table, and page number. Send comments to
Lake Shore Cryotronics, Attn: Technical Publications, 575 McCorkle Blvd.,
Westerville, Ohio 43082-8888. This manual is subject to change without
notice.

1.1 MODEL 102 GENERAL DESCRIPTION

The Model 102 is a precision DC current source which provides excellent
performance at low cost. The factory pre-sets output current to 10 µA, but
the unit may be reprogrammed at any value between 1 µA and 1 mA by
changing a resistor inside the instrument.

The Model 102 has a compliance voltage of 8 Volts, allowing it to be used as
an excitation source in a variety of diode sensor applications. A compliance
LED visually indicates unit operation within specification.

The Model 102 provides a constant current through the load (sensor)
connected across the output terminals. It monitors the voltage across the
sensor and derives a corresponding temperature from the response curve
supplied with the sensor.

An external AC wall-mount transformer supplies power to the unit. There
are two 12 VAC wall mount transformers available for the Model 102: a 120
VAC to 12 VAC transformer for a 90

– 130 VAC input, and a 220 VAC to 12

VAC transformer for a 200 – 250 VAC input. Specify the supply type to match
the AC line voltage when ordering.

Introduction 1-1

Lake Shore Model 102 User’s Manual

Table 1-1. Model 102 Specifications

Output Current: 10 µA factory set; internally programmable

from 1 µA to 1 mA.

Accuracy: 0.05% of output at 10 µA

Temperature Coefficient: 0.005% per °C

Compliance Voltage: 8 volts

AC Current Ripple: Less than 0.01% of scale +1 nA (RMS) in a

properly shielded system

Line Regulation: Less than 0.01% change in output for

10% change in line voltages within specified range

Load Regulation: Less than 0.01% change in output current

from 1 to 100% of compliance voltage

Connections: Current output via standard banana jacks

Ambient Temperature Range: 15 – 35 °C (59 – 95 °F)

Power: 90 – 125 or 210 – 250 VAC, 50/60 Hz,

External Wall Mount AC Transformer

Size: 95 × 33 × 158 mm (3.7 × 1.3 × 6.2 inches)

Weight: 0.3 kilograms (0.7 pounds)

NOTES

1. Product Specifications are subject to change without notice.

2. The electrical specifications given are for a unit operating at the

factory at current output of 10 µA; a different output current may
affect some specifications.

1-2 Introduction

Lake Shore Model 102 User’s Manual

1.2 HANDLING LIQUID HELIUM AND LIQUID NITROGEN

Helium and Nitrogen are colorless, odorless, and tasteless gases. They
liquefy when properly cooled. Liquid Helium (LHe) and liquid nitrogen (LN

)

2

may be used in conjunction with the Model 102. Although not explosive,
there are certain safety considerations in the handling of LHe and LN

.

2

1.2.1 Handling Cryogenic Storage Dewars

Operate all cryogenic containers (dewars) in
accordance with manufacturer instructions. Safety
instructions are normally posted on the side of
each dewar. Keep cryogenic dewars in a well­ventilated place, protected from the weather, and
away from heat sources. Figure 1-1 shows a
typical cryogenic dewar.

1.2.2 LHe and LN

Transfer LHe and LN

Safety Precautions

2

and operate storage dewar

2

MAGNETIC

LIQUID

HELIUM

NON-

KEEP

UPRIGHT

NON-

FLAMMABLE

controls in accordance with manufacturer/supplier
instructions. During transfer, follow all safety
precautions written on the storage dewar and
recommended by the manufacturer.

Figure 1-1. Typical

Cryogenic Dewar

WARNING

• Liquid helium is a potential asphyxiant and can cause rapid
suffocation without warning. Store and use in an adequately
ventilated area. DO NOT vent the container in confined spaces. DO
NOT enter confined spaces where gas may be present unless area
is well-ventilated. If inhaled, remove to fresh air. If not breathing,
give artificial respiration. If breathing is difficult, give oxygen. Get
medical attention.

• Liquid helium can cause severe frostbite to exposed body parts. DO
NOT touch frosted pipes or valves. For frostbite, consult a
physician immediately. If a physician is unavailable, warm the
affected parts with water that is near body temperature.

Two essential safety aspects of handling LHe are adequate ventilation and
eye and skin protection. Although helium and nitrogen gases are non-toxic,
they are dangerous because they replace air in a normal breathing
atmosphere. Liquid helium is an even greater threat because a small amount
of liquid evaporates to create a large amount of gas. Store and operate
cryogenic dewars in open, well-ventilated areas.

Introduction 1-3