ALTONOVUS OR-01 User manual

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OR-01 Instruction Manual V1.0 dated 14 Mar 22 –OR Software V2.20 and above
Instruction Manual
OR-01 Low Compliance Voltage Ohmmeter

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OR-01 Instruction Manual V1.0 dated 14 Mar 22 –OR Software V2.20 and above
Disclaimer
ΩhmRanger-LCV™ is a factory-calibrated, accurate low compliance voltage ohmmeter, intended
for measuring resistance without subjecting the Device Under Test (DUT) to excess stimulus
voltage. It is aimed at both the professional and the enthusiast User. ΩhmRanger-LCV™ is not
intended to replicate the full functionality of expensive laboratory equipment. Instead, it aims to
provide a portable and affordable means of measuring the resistance of delicate components,
where this has in the past required engineers to develop their own rigs.
If used in any manner other than that expressly set out in the AltoNovus product documentation,
warranties granted by AltoNovus shall be deemed void and AltoNovus shall not be liable for any
claims, or damages arising out of product misuse or malfunction.
Although every effort is made to ensure the accuracy of ΩhmRanger-LCV™, no guarantee of
accuracy is given or implied, or responsibility accepted for consequential loss. Users may
reproduce and store this document for personal use. For wider permission requests, email the
publisher, addressed “Attention: Permissions Coordinator,” at i[email protected]. The name
ΩhmRanger-LCV™ is Trademark 2022 AltoNovus Limited. The name ΩhmRanger-LCV™ will
be a Registered Trademark of AltoNovus Limited.
Document Revisions
DATE
VERSION NUMBER
DOCUMENT CHANGES
14 Mar 22
1.0 (Software Release 2.20)
Launch Release
Approvals - Release / amendment of this document requires the following approvals:
NAME
ROLE TITLE
Geoff Dean
Managing Director
Steve Thickett
Technical Director

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OR-01 Instruction Manual V1.0 dated 14 Mar 22 –OR Software V2.20 and above
TABLE OF CONTENTS
1Preface................................................................................................................................5
1.1 The User..............................................................................................................................5
1.2 Conventions Used in This Manual.......................................................................................5
1.3 Explanation of Safety Warnings...........................................................................................5
1.4 Obtaining Documentation and Information..........................................................................5
2ΩhmRanger-LCV™ ............................................................................................................6
2.1 Utility and Employment........................................................................................................6
2.2 Theory of Operation.............................................................................................................6
2.3 Technical Data.....................................................................................................................8
2.4 Compliance..........................................................................................................................9
2.5 Guide to Product..................................................................................................................9
2.6 Understanding the User Interface........................................................................................9
2.7 Device Set-Up....................................................................................................................10
2.8 ΩhmRanger-LCV™ Menu Structure..................................................................................12
3Safety................................................................................................................................15
3.1 Using ΩhmRanger-LCV™ Safely ......................................................................................15
3.2 Guide to Graphical Symbols..............................................................................................16
4Taking Manual Readings ................................................................................................18
4.1 Switch ΩhmRanger-LCV™ ON .........................................................................................18
4.2 Automatic Range-Switching...............................................................................................18
4.3 The Signal to Noise Ratio (SNR).......................................................................................18
4.4 Switching ΩhmRanger-LCV™ OFF...................................................................................19
5Getting Connected - taking PC-Controlled Readings & SCPI Commands................20
5.1 SCPI Mandated Commands:.............................................................................................20
5.2 SCPI Required Commands: ..............................................................................................21
5.3 Device Commands (Routine Use).....................................................................................21
5.4 Device Commands for Advanced Use only (not normally required)..................................23
6Storage, Transportation and Disposal ..........................................................................25
6.1 Storage ..............................................................................................................................25
6.2 Packaging and Transportation...........................................................................................25
6.3 Disposal.............................................................................................................................25

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OR-01 Instruction Manual V1.0 dated 14 Mar 22 –OR Software V2.20 and above
7Maintenance.....................................................................................................................26
7.1 Replacing the Batteries......................................................................................................26
7.2 Cleaning.............................................................................................................................26
7.3 Recalibration......................................................................................................................26

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OR-01 Instruction Manual V1.0 dated 14 Mar 22 –OR Software V2.20 and above
1 Preface
1.1 The User
ΩhmRanger-LCV™ is not a toy. It is a precision instrument and should be treated accordingly.
It is aimed at the professional and enthusiast User community. This Instruction Manual
assumes a level of technical expertise on the User’s part. ΩhmRanger-LCV™ should not be
used by those without a knowledge of safe working on electronics. This Manual covers the use
and operation of ΩhmRanger-LCV™. It does NOT cover calibration or maintenance (beyond
battery replacement or routine cleaning), as these are not activities that the User can perform.
1.2 Conventions Used in This Manual
The following style conventions are used in this document:
Courier New
SCPI System control inputs and outputs.
User input variables
< > Angle brackets surround User-supplied values.
1.3 Explanation of Safety Warnings
CAUTION! Indicates a hazard with a low level of risk which, if not avoided, could result in damage
to ΩhmRanger-LCV™ and / or minor injury to Users.
1.4 Obtaining Documentation and Information
1.4.1 Internet
The latest version of the documentation and any software updates are available at the following
web address: http://www.altonovus.com.
1.4.2 Ordering Documentation
Documentation, User instructions and technical information can be requested by emailing:
[email protected].
1.4.3 Documentation Feedback
We welcome your comments and ideas, which may be incorporated in a ΩhmRanger-LCV™
FAQs page. Any comments, requests for clarification, or suggestions for future Versions of this
document can be submitted to: [email protected]m.

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OR-01 Instruction Manual V1.0 dated 14 Mar 22 –OR Software V2.20 and above
2 ΩhmRanger-LCV™
2.1 Utility and Employment
ΩhmRanger-LCV™ is an accurate, affordable, low compliance voltage ohmmeter, for the
measurement of resistance of components that cannot be exposed to large stimulus voltages.
One example is the delicate Josephson Junction that forms the ‘transistor equivalent’ of some
quantum computers. Previously, engineers have been required to develop their own
measurement rigs to test such components.
The ΩhmRanger-LCV™ is a solution to this challenge, as it provides accurate measurement
from >100M to 10 Ohms, with a stimulus voltage always less than 400mV. It features:
•Low stimulus voltages, selectable between approximately 380mV or approximately 206mV, with
on-screen voltage confirmation.
•Stimulus voltage at the output terminal is limited by the maximum current supply of approximately
30mA.
•Readings from >100M to 10 Ohms.
•A 128 x 64 LCD display gives a wealth of information about your Resistance readings.
•A large display shows MΩ, KΩ, and Ω, all on one line.
•Readings every 400mS, built up from 160 samples and averaged to tune out mains noise (both
50 Hz and 60 Hz).
•Fully isolated USB Interface for device control and readings export.
•SNR display to indicate noise level on signal.
•Range Bar movement after every reading to show that ΩhmRanger-LCV™ is operating correctly.
•Range Coverage Bar that shows the ranges covered during the measurement.
•User-configurable Auto Power-off timer.
•A small form, with dimensions of 148 x 90 x 30mm, making ΩhmRanger-LCV™ highly portable.
•150 hours of operation on 2 x AA batteries.
•An automatic Power Off timer, and configurable LED backlight, enabling the User to maximise
battery life.
Readings are completed approximately every 400mS and the display is updated, with samples
collected and averaged out to remove most of the mains noise associated with circuits (50Hz and
60Hz).
2.2 Theory of Operation
ΩhmRanger-LCV™ is powered by 2 x AA batteries (not supplied), generating approximately 3V (but
will continue to work down to approximately 2V on the batteries).
Pressing the Power On button starts the ΩhmRanger-LCV™. Pressing the Power On button again
powers off the ΩhmRanger-LCV™. Standby current, when powered off, is approximately 10nA.

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OR-01 Instruction Manual V1.0 dated 14 Mar 22 –OR Software V2.20 and above
The ΩhmRanger-LCV™ is developed from AltoNovus’ NanoRanger, which is an auto-ranging
ammeter used to measure low currents, with great accuracy, through decadal ranges.
ΩhmRanger-LCV™ has an additional, readable voltage source.
The stimulus voltage selected is output on the Positive terminal of the ΩhmRanger-LCV™ and
the resistance to be measured is connected across the terminals. The two voltage outputs that
can be selected by the User are approximately 380mV and 206mV. The actual voltage output is
displayed on the device screen.
ΩhmRanger-LCV™ measures the current coming in through the Negative terminal by measuring
the voltage across an internal range resistance. The ΩhmRanger-LCV™ can measure currents
down to 1nA by switching in different range resistances. The device has 9 internal range
resistances used to measure current, with a 40mV full scale burden voltage. The maximum
current we can measure (together with the associated range resistance) per range is:
Range Number
Internal Range Resistance
Max current @40mV
0
2MΩ
20.00nA
1
200KΩ
200.0nA
2
20KΩ
2.000uA
3
2KΩ
20.00uA
4
200Ω
200.0uA
5
20Ω
2.000mA
6
2Ω
20.00mA
7
0.2Ω
200.0mA
8
0.05Ω
800mA
The resistance is computed by dividing the output voltage by the measured current (R=V/I)
before subtracting the range resistance. Factory set calibration compensation is applied to
both current and voltage, to give an accurate reading of resistance. i.e. R_TOTAL = R +
R_INTERNAL = V/I. In the example shown on the screen below:

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OR-01 Instruction Manual V1.0 dated 14 Mar 22 –OR Software V2.20 and above
R + R_INTERNAL = 0.2067V / 89.8nA (here using Range 1, where the associated Range
Resistance is 200KΩ). Therefore:
R + 200KΩ= 2.3MΩ, and
R = 2.3MΩ–200KΩ= 2.1MΩ
For clarity, the User can see the 3 values above V (206.7mV), I (89.8nA), and the Range (1) on
the display in real time, and live, during measurement, as shown above.
Please Note: Although range 8 exists in the OhmRanger, because the current is limited to
approx. 30mA we will never switch up to that range from the 200.0mA range.
2.3 Technical Data
UNIT
PHYSICAL PARAMETERS
Weight (not including batteries)
Approximately 200g
Length x Width x Depth
148 x 90 x 30 mm
Accuracy specifications +/- % of range:
RESISTANCE
ACCURACY
>100MΩ
5%
1-100MΩ
2%
100-1MΩ
1%
<100Ω
2%
•Current consumption LCD Light on < 15mA.
•Current consumption LCD Light off < 10mA.
•Current consumption Powered-off < 10nA.
•Typical operating time on one set of 2 x AA batteries is > 150 hours.

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OR-01 Instruction Manual V1.0 dated 14 Mar 22 –OR Software V2.20 and above
UNIT
OPERATIONAL PARAMETERS
Temperature
0 –50C
Humidity
10 –90% non-Condensing
2.4 Compliance
ΩhmRanger-LCV™ is certified UKCA, CE and FCC compliant. A supporting Technical File is
available to Competent Authorities on request.
2.5 Guide to Product
A - Positive Terminal
B - Negative Terminal
C - Display Screen
D - On / Off Button
E - Menu Navigation
F - Select Button
G - Isolated USB Interface
H - Battery Compartment
2.6 Understanding the User Interface
A - The Resistance reading, displayed in MΩ, KΩ and Ω. In the example above, 2.1MΩ.
B - A small, oscillating Range Bar shows which range is currently in use. An upper, longer Range
Coverage Bar shows any movement across the ranges during the reading (in this example,
none). The box surrounding shows the operating range.

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OR-01 Instruction Manual V1.0 dated 14 Mar 22 –OR Software V2.20 and above
C - The Voltage being applied by ΩhmRanger-LCV at the Positive terminal, in this case
206.7mV, to measure the resistance.
D - The active Range and the observed Current.
E - The Signal to Noise Ratio (SNR). The SNR indicates how much noise, variation, and AC
components are in the signal, followed by Maximum and Minimum Current samples during the
reading. Higher resistances (lower currents) are more susceptible to noise. In this example
currents ranged from 102.2nA down to 77.1nA. At these current levels mains pickup in the test
leads are the biggest source of noise.
2.7 Device Set-Up
2.7.1 Fitting 2 x AA Batteries
1. Remove battery compartment cover, by applying gentle pressure
to the finger pad.
2. Ensure clean contacts on batteries.
3. Insert new batteries, observing polarity instructions in battery
compartment:
4. Replace battery compartment cover.
Note: 2 x AA alkaline batteries should give more than 150 hours of continuous operation. Treat
and dispose of all batteries in accordance with manufacturer’s instructions.
2.7.2 Removing the Protective Film
If desired, remove the protective film from the front of ΩhmRanger-LCV™. Peel carefully
from below the Positive and Negative terminals. ΩhmRanger-LCV™ will still function
normally if the User chooses to leave the film in place.
2.7.3 Attach Feet (if desired)
ΩhmRanger-LCV™ is supplied with 4 rubber feet, for Users requiring added stability. Attach
these with due regard to the areas that will experience pressure during normal use; i.e. the
Keypad buttons and Terminals. Attaching the Feet as shown below will improve the stability of
ΩhmRanger-LCV™ during use.