LabSmith HVS448 User manual

LabSmith HVS448 High Voltage Sequencer
User Guide
Version 1.5
For operation and control of LabSmith HVS448™ High Voltage Sequencer and
Sequence™ Driver Software

This manual © 2020 LabSmith. Sequence Software ©2002-2020 LabSmith, Inc.
No part of this document may be reproduced or distributed without the consent of LabSmith.
LabSmith, HVS448 and Sequence are trademarks of LabSmith, Inc.
Microsoft, Windows are registered trademarks of Microsoft Corporation.
Adobe and Acrobat are registered trademarks of Adobe, Inc.
LabVIEW is a trademark of National Instruments, Inc.

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TABLE OF CONTENTS
CHAPTER 1. INTRODUCTION 5
How You Will Use the HVS448 5
Equipment List 5
Cautions and Warnings 6
Getting Help 6
About This Manual 6
CHAPTER 2. GETTING STARTED 7
Installing Sequence Software 7
Grounding the HVS448 Channels 7
Master Interlock Input 8
Disable/Enable High Voltage 8
High Voltage Connections 8
Setting Up the HVS448 Hardware for Operation 9
Using the Sequence Wizards to Create a Sequence File 9
Simple Sequence Wizard 9
Complex Sequence Wizard 11
Running a Sequence 11
CHAPTER 3. HVS448 HARDWARE 13
Front Panel Controls 13
Front Panel LEDs 14
Locking the Front Panel Controls 14
Back Panel Connections 14
Digital Connections 14
Recalibrating the Channels 15
CHAPTER 4. SEQUENCE SOFTWARE OVERVIEW 16
Field Upgradeable Firmware 16
Sequence Files 16
Online and Offline Operation 16
Sequence Software Environment 16
Monitor Settings 17
CHAPTER 5. HIGH VOLTAGE POWER SUPPLY: MANUAL MODE 18
Channel Control Panels 18
Channel Status 18
Channel Settings 18
Channel Output Limits 19
Error Reporting/Trip Settings 19
Manual Power Supply Control Panel 20
Overall Settings 20
Monitoring 20
Channel Settings 20
Error Flags 21
View Channel Settings in the Left Pane 21
Using Trace Measurements to Record Data 21
CHAPTER 6. HIGH VOLTAGE SEQUENCING: AUTOMATED MODE 22
Master and Channel Sequencers 22
Manual Changes During an Automated Sequence 22
Inter-Channel Communication 22
Step Instructions 22
Orderly Step Flow 23
Step H: The Exit Step 23

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Flags 23
Triggers 23
Sequence and Program Flow 24
Monitoring and Interacting with an Automated Sequence 25
Sequencer Control Panel 25
Channel Sequence Control Panels 26
The Programming Interface 27
Editing Sequences 28
View and Edit Instructions in the Left Pane 28
View and Edit Instructions in the Right Pane 28
Edit with the Programming Keypad 29
Error Checking and Parsing 30
CHAPTER 7. CHANNEL PROGRAM INSTRUCTIONS 31
Nomenclature 31
Execution Controls 31
Inter-channel Signaling and Triggering 33
Channel Functions 35
Register Functions 36
Calculator Functions 37
Reverse Polish Notation and the Numerical Stack 37
Integral Representation of Real Numbers 37
Conditional Tests 40
APPENDIX 1. MENUS AND TOOLBARS 42
Menu Functions 42
Toolbars 43
APPENDIX 2. HVS448 SYSTEM ARCHITECTURE 44
APPENDIX 3. PROGRAMMING EXAMPLE 45
Setting up the Experiment 45
Writing the Sequence 45
Running the Sequence 47
APPENDIX 4. TROUBLESHOOTING –COMMON OPERATIONAL ERRORS 48

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CHAPTER 1. INTRODUCTION
The HVS448 High Voltage Sequencer provides eight coordinated channels of high voltage sourcing and sensing, with a powerful
sequencing environment that lets you quickly automate complex experiments. You can set each channel independently
(manually or automatically) to supply voltage, supply current, or float at high input resistance, all while continuously monitoring
the voltage and current. The maximum supplied voltage, current, measurement resolution and input resistance depends on the
model (Table 1).
The included Sequence™ software lets you automatically set the functions and parameters of each channel. The set of
automation commands, called a sequence, is constructed from smaller programs that control particular events. Each channel
runs its own independent sequence, and channels can also communicate state changes to each other, and respond to external
events. The settings and programming for a particular experiment can be stored as a sequence file on your computer.
Table 1. LabSmith HVS448 High Voltage Sequence Available Models.
Model
Max Output
Voltage
[+V]
Max Voltage
Differential
[V]
Max Output
Current
[+mA]
Max Output
Current Per
Channel [+mA]
Current
Monitor
Resolution [nA]
Voltage
Monitor
Resolution [mV]
8000D
4000
8000
2.5
1.8
250
150
8000D-LC
4000
8000
0.72
0.09
13
150
6000D
3000
6000
3.2
2.4
300
100
6000D-LC
3000
6000
0.96
0.12
15
100
3000
3000
3000
6.0
4.8
300
100
3000-LC
3000
3000
1.9
0.24
15
100
3000D
1500
3000
6.0
4.8
500
50
3000D-LC
1500
3000
1.9
0.24
25
50
1500
1500
1500
12
10
500
50
1500-LC
1500
1500
4.0
0.50
25
50
800
800
800
25
20
1000
25
400
400
400
50
40
2000
12
200
200
200
100
80
4000
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How You Will Use the HVS448
In manual mode, you can independently set and monitor the eight channels of the HVS448 using the Sequence™software
interface or with other software such as LabVIEW®.
In automated mode, you will enter a series of program steps and store the steps in a sequence file. The program can then be
recalled and run using the HVS448 front panel, or with the Sequence™ software.
Equipment List
Your HVS448 package should include the following items:
-The HVS448 sequencer
-AC power cable
-USB flash driver with Sequence™ software
-9-pin RS232 cable
-50-Ω Terminator
-HVS448 User’s Manual.
You may have also ordered and received these recommended items:

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-Set of 8 HVS High Voltage Cables
-Set of 8 microclip connectors
-Platinum electrodes
-RS232-to-USB adapter, to control the HVS448 from a computer without a RS232 port.
If any items are missing or damaged please contact LabSmith support ([e-mail].)
Cautions and Warnings
LabSmith, Inc. believes that the HVS448 product information enclosed is an accurate description of the typical characteristics
and uses of the product, but it is your responsibility to thoroughly test the product in your specific application to determine its
performance, efficacy and safety in your conditions of use.
Standard lab safety rules should always be applied: keep the unit away from liquids and excessive heat, leave space around the
unit for heat dissipation, etc.
Understand the characteristics of the inputs and outputs of the HVS448 before connecting other equipment. Failure to do so
may result in damage to the HVS448 or to external devices.
WARNING The HVS448 is a high voltage power supply and thus presents a serious risk of personal injury if not
used in accordance with design and/or use specifications, if it is used in applications for it is not
intended or designed, or if it is used by untrained or unqualified personnel. Before testing,
incorporating or using the HVS448, understand and adhere to all applicable instructions, protocol,
cautions and safety procedures.
Getting Help
This guide is your main source for information on operating the HVS448 and Sequence software. Choose Help>About Sequence,
then click the Open User Manual link to browse this manual electronically, in Adobe® Acrobat®PDF format.
The LabSmith web site (www.labsmith.com) also includes helpful applications notes and other technical information to help
you use the HVS448. If you are unable to find the information you need, please contact our technical support team at (925) 292-
5161, or email us at [email protected]. Be prepared to give the HVS448 serial number (located on the bottom of the unit),
software version and firmware version you are using. To determine the software version number, select Help>About Sequence.
To verify the firmware version, go to Action>Get Versions. The firmware version number will be displayed in the status bar. The
unit must be Online for the firmware version to be displayed.
About This Manual
Several conventions are used throughout this manual to highlight important features and concepts:
Menu>Option Menu bar selections are shown in bold text, with descending options separated by the “>” symbol. For
example, Help > About Sequence indicates that you should click the Help menu, then click About
Sequence.
Note Notes indicate helpful tips or additional information.
CAUTION These notes will help you to avoid losing data or damaging hardware.
WARNING These important notes indicate situations that could result in injury or serious equipment damage. Read
and understand all warnings before operating the HVS448.
If you find any errors or omissions in this manual please let us know at suppo[email protected].

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CHAPTER 2. GETTING STARTED
Installing Sequence Software
Sequence software runs on any PC-compatible computer running Microsoft Windows®XP or newer. To install Sequence
software:
1. Insert the Sequence for Windows CD (or download the software from www.labsmith.com/support/hvs448-high-
voltage-sequencer).
2. Double-click SETUP.EXE and follow the on-screen instructions.
To run the software, double-click the Sequence icon on your desktop, or choose LabSmith>Sequence>Sequence from the Start
menu.
Grounding the HVS448 Channels
The chassis and the grounds of all the channels are electrically connected to the ground pin of the HVS power connector. Only
connect the HVS to a properly grounded outlet. You have several options for properly grounding the HVS:
-Connect a wire between the grounding pin of on the back of the HVS and other apparatus (e.g., microscopes, etc.) to
ensure that all equipment remains at safe voltages despite experimental errors or problems.
-Connect the HVS to ground using one channel or the grounding pin, then use another channel to ground another
instrument. This method ensures that the HVS high-voltage signal does not cause voltage across another instrument.
-Attach the grounding pin to a grounding cable to ground all channels.
-If using LabSmith’s HVC cables, the HVS448 can be grounded by attaching any one of the grounding leads to a ground
source.
WARNING Do not handle cable terminations or clips while they are connected to an energized circuit. The micro-
and nano-clips do not protect from high voltage. The clips are not designed to be handled when high
voltage is present. When using the clips, use the same safety precautions as you would with an
exposed electrode.
Cable ends and clips should be housed in an interlocked enclosure to protect the user from accidental exposure to the high
voltage circuit (Figure 1).
High voltage cables and clips present a serious risk of personal injury if not used in accordance with design and/or use
specifications, if they are used in applications for products for which they are not intended or designed, or if they are used by
untrained or unqualified personnel. Before testing, incorporating or using the cables with the HVS448, understand and adhere
to all applicable instructions, protocol, cautions and safety procedures.
Figure 1. Diagram of LabSmith HVC High Voltage Cables, Shown Grounded and in Interlocked Chamber for Safe Operation.
Note: Grounding any channel or the chassis grounds all of the channels. Using the grounding cable attached to the channel
you are applying voltage to may give you less noise then grounding the chassis or a different channel. If noise is a
concern, you should use a grounding wire at each channel to which you are applying high voltage.

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Master Interlock Input
The Interlock inputis the center terminal of a BNC connector located on the back panel of the HVS448. The interlock signal is
TTL-compatible (0–5 V) and weakly pulled to 5 V via an ~20 kΩinternal resistor. When the interlock signal is in its high state (>0.8
V), the high voltage connectors are disconnected from the power supply by relays, and the internal high voltage supply is turned
off. Because of the internal pull-up, a high state can be maintained by leaving the signal open.
High voltage is enabled by maintaining a TTL low signal (<0.2 V) to the interlock. This can be accomplished by connecting the
supplied 50-Ω terminator (Figure 2) to the interlock connection,connecting to an interlock switch to ground, or connecting to a
digital interlock signal that is active low.
To test if the interlock is satisfied (low): on the front panel click the Enable then All buttons. If the interlock is satisfied this will
enable the high voltage and turn on a green light over the All button. If the light is red, the interlock is not satisfied.
Figure 2. 50-Ω BNC Terminator for Interlock
Disable/Enable High Voltage
Disabling high voltage is a quick way to place the system in a “safe” state. The high voltage connectors on the back panel will
float to the driving voltage when disabled, regardless of the sequence or the states of other channels. High voltage can be
enabled or disabled from the software or using front panel controls. This setting is nonvolatile and is remembered on power-up.
Disable High Voltage:
•From the front panel, push Disable, then All;
•or, from the software click the Disable High Voltage toolbar button or , choose Actions>Disable High Voltage.
When the high voltage is disabled the LED over the ALL button will turn off, or will glow red if the Interlock is not satisfied.
Enable High Voltage:
•From the front panel, push Enable, then All;
•or, from the software, click the Enable High Voltage toolbar button or choose Actions>Enable High Voltage.
When the high voltage is enabled the LED over the ALL button will glow green if the interlock is satisfied or red if the Interlock is
not satisfied.
High Voltage Connections
Each channel of the HVS448 includes a single high voltage connector. Each channel can function as a voltage/current source or
monitor, so this connector acts as either an input or output, depending on the function of the channel at any time.
The total system output (all channels considered) will not exceed the maximum unit current (see Table 1). The system will
automatically shut down the high voltage supplies if this current is exceeded. Each channel’s maximum and minimum voltage
and current can be limited in software to protect external devices and equipment (see Channel Output Limits). Under no
condition will the voltage or current at the channel connection exceed these software limits.
WARNING: DO NOT connect or disconnect cables from an enabled high voltage channel. Doing so could result in
personal injury and/or damage to the HVS448 or external equipment. You must disable the high
voltage connectors or turn off the HVS448 before plugging or removing equipment. Use the Disable
HV button on the toolbar or select Actions> Disable High Voltage from the dropdown menu tab.
WARNING: Do NOT connect a high voltage channel to a digital input or output. While the digital inputs and
outputs are protected to 115 VAC, connecting these different voltage levels could damage the HVS448
and/or any connected equipment.

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Setting Up the HVS448 Hardware for Operation
1. Ground your HVS448 using any of the methods recommended above.
2. Connect the 50 Ω terminator into the master interlock
3. Plug the power cable from the back of the HVS448 into a 90–250 VAC power outlet.
4. Connect the RS232 cable to the back of the HVS448 and to a free serial port on the PC.
Note: If connecting to a computer without a RS232 port, use a RS232-USB adapter and attach to the computer’s
USB port.
5. Press the Power button on the front of the HVS448.
6. From your computer, run the Sequence software.
7. From within Sequence, select View>Options>Communications. The Serial Communications dialog box will open
(Figure 3).
8. Select the COM port to which the HVS448 is connected and click OK.
Figure 3. Serial Communications Dialog Box
Using the Sequence Wizards to Create a Sequence File
Sequence Wizards simplify the process of creating sequences by letting you enter voltages and currents directly for each step of
the sequence. A sequence can contain up to 20 steps, with settings for up to 8 channels. These settings, and all the programming
instructions necessary to automatically set up each channel, are stored in a Sequence file with a .seq extension.
Simple Sequence Wizard
The Simple Sequence Wizard lets you apply/measure DC current and voltage. To use the Simple Sequence Wizard:
1. Open the Sequence software if it is not already opened.
2. Select Tools > Simple sequence wizard. The Wizard interfaces contain tabs for each step (Figure 4). When you launch a
wizard the settings for Step A will be displayed. Click on any step’s tab to view that step’s settings.
3. In the Step Name field, enter a name which easily identifies the step. The name must begin with a capital letter and
contain only letters, numbers, “.” or “_”.

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Figure 4. Simple Sequence Wizard Window
4. Set the Switch step settings to specify the condition at which the sequence will move from the current step to the next
step in the sequence:
a. Select Only manually to switch steps manually, using the Master Controller (see Sequencer Control Panel).
b. Select After delay, enter a time period (in milliseconds), and select the Next Step to which the sequence should
jump after that specified time.
c. Select After trigger, choose the condition that will trigger a step change, then select the Next Step to which the
sequence should jump when the trigger condition occurs. The trigger conditions can be a high or low TTL signal
at any of the four inputs In1 –In4.
5. Enter the setting changes for each channel during this step:
a. Select Unchanged to leave the channel in the same state as the previous sequence step.
b. Select Input to use the channel as a voltmeter for an incoming signal.
c. Select D.C. Voltage, then specify the voltage for the channel to maintain during this step. You can set the
voltage by entering the value in the box or by dragging the slider. If you are running in constant current mode,
you do not need to specify this value.
6. Complete 1-4 for each of the steps in the sequence.
7. Click Apply to send the program to the HVS448.
8. Choose File>Save, then specify a location and file name to which to save the sequence file. It will be saved as a “.seq”
file.
Note: Once a file name has been specified, click OK to save the program and send it to the HVS448.

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Complex Sequence Wizard
The Complex Sequence Wizard (Figure 5) provides the same Name, Next Step and DC operations as described in the Simple
wizard above. It also gives you the ability to apply a low frequency (1 kHz), sine, cosine, triangular or sawtooth wave to the
applied voltage.
Figure 5. Complex Sequence Wizard
For AC operations, click the radio button labeled Waveform next to each channel to open the Waveform Generation dialog box
(Figure 6).
Figure 6. Complex Sequence Wizard: Waveform Generation dialog box
Choose the Waveform shape you wish to apply, then set:
-Offset (V), the DC offset (if any) applied to the waveform.
-Amplitude (V), the peak to peak voltage differential of the waveform.
-Period (ms), the duration of a single cycle of the waveform. The maximum frequency that can be applied is 1 kHZ.
-Phase Delay (ms), the delay after a sequence step starts until the waveform begins, and
-Number of voltage settings per cycle, the number of times per cycle that the voltage will be updated.
Note: By default, generated waveforms are bipolar (i.e., they oscillate between negative and positive voltages). When a
unipolar waveform is required (for example, a 0 to 5 V square wave) the offset and amplitude controls together can be
used to adjust the output accordingly.
Note: For high-frequency waveforms: (1) turn off channel monitoring, as monitoring can periodically interrupt the generation
of the waveform and degrade the performance; and (2) set the sampling rate to 0.4 ms (minimum setting).

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Running a Sequence
To run the saved sequence:
1. Select the sequence file (File>Open) if it is not already selected.
2. Click the Online/Offline toolbar button to toggle the software online (see Online and Offline Operation).
3. Click the Enable toolbar button to enable voltage (see Disable/Enable High V).
4. Send the settings to the HVS448.
a. If the HVS448 is brought online after the program is written and saved, you will see the HVS is Online dialog
box (Figure 7). Check the Send the current sequence program to the HVS448 now box.
b. If the HVS448 was online prior to programming choose Actions>Program All.
5. In the left pane click Sequence to open the Sequencer Control Panel.
6. Press Aat the bottom of the Sequencer Control Panel to run Step A, etc. If you selected timed events or triggers, then
the automated sequence you created will take over. If not, and you selected “manual” to switch between steps in the
Sequence Wizard, click the icon in the left pane. The Manual Sequence Monitor and Control (Figure
8) will open in the right pane.
7. Switch between Steps A-H manually by using the cursor to select a step and left clicking on the mouse.
Figure 7. HVS448 is Online Dialog Box
Figure 8. Manual Sequence Monitor and Control window

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CHAPTER 3. HVS448 HARDWARE
Most control of the HVS448 sequencer occurs through the Sequence software environment. The HVS front panel (Figure 9) also
includes several important functions that let you use the unit without a computer.
Figure 9. HVS448 Front Panel (3000V model shown)
Front Panel Controls
The Power button and Power LED are located in the upper left corner of the front panel. During power up the LED will flash green
and red while the system runs its initial diagnostics.
While the programming of the HVS448 must be done on a computer, once a sequence file has been sent to the HVS448, it can be
operated using the front panel buttons. The front panel buttons typically work in pairs, by either of two methods:
1. Select a channel or step (A–H) and then select a function to perform on that channel/step. When you select the
channel/step, its LED will remain lit until you select a function. Push the channel/step button again to deselect it.
2. Select a function, then select the channel(s) to apply that function to. The function button will remain lit after you select a
channel, indicating that you can select additional channels. Push the function button again to deselect it. Selecting a
different function will also deselect the first function.
The front panel controls are as follows:
A–HSelect individual channels or sequence Steps, A–H.
All Select all channels/steps, so you can apply a function to all of them at once.
Enable/Disable Enable/disable the channels (see Disable/Enable High V)
Trigger Force the trigger of a channel. The trigger only affects an Await Trigger function in that channel’s sequence.
(see Inter-Channel Communication).
Push Trigger, then ALL, to trigger the Master sequencer, which has authority over individual channel
sequencers.
Pause Pause the current sequence. All channels will remain frozen in their last state. Press the button again to
resume the sequence. You do not need to select a channel or step before pushing Pause.
Run Jump to the selected Step, A–H, in the sequence.
Stop Stop the sequence if one is running and set all high voltage channels to be inputs (i.e., they neither source
nor sink current). You do not need to select a channel or step before pushing Stop.

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Front Panel LEDs
The front panel LEDs provide information on the state of the channel or the unit. The channel indicators were modified in version
1.153 of the SequenceTM software to improve HVS448 performance. Table 1 below shows the standard LED settings. During the
execution of a sequence, the master sequencer can be programmed to override any channel or the ALL LED setting (however this
may adversely affect the unit performance). This would be used, for example, to indicate the execution status (see LED).
Table 2 Front Panel LED Settings
LED
Status
Sequence v1.152 and previous
Channel A-H
Sequence v1.153 and later
Channel A-H
All Versions of Sequence
Channel ALL
Green
channel is sinking current (current
is flowing into the channel)
channel is sinking or
sourcing
high voltage is enabled
Red
channel is sourcing current (current
is flowing out of the channel)
error has occurred (such as
overvoltage or
overcurrent)
high voltage is disabled, for example
because of an open interlock or over-
current
Off
channel is an input (not sinking or
sourcing current)
channel is an input or off
high voltage has been manually
disabled
Yellow
N/A
N/A
HVS448 is switching the high voltage on
or off or changing the voltage ranges
Locking the Front Panel Controls
The front panel controls can be locked to prevent users from adjusting sequences or triggering a program. To lock the front
panel, choose Actions> Lock Front Panel from the Sequence software. When the panel is locked, the LED next to the power
button glows a steady red and all buttons are dark.
The front panel can be unlocked by choosing Actions>Unlock Front Panel. This is the default condition. When the panel is
unlocked, the power LED glows green and the front panel buttons are illuminated.
The Lock functions are nonvolatile: the panel will remain locked or unlocked even if power is removed and restored. The panel
can only be unlocked from within the Sequence software.
Back Panel Connections
The back panel of the HVS448 houses the following connections
Power input Plug the power cable from the back of the HVS448 into a 90–250 VAC power outlet
RS232 socket A RS232 cable is used to connect the HVS448 to a RS232 port on the host PC. Alternatively, a
USB-to-serial adapter can be used with the RS232 cable to connect to a USB port on the PC.
Grounding pin Used to ground HVS448 unit (see Grounding the HVS448 Channels)
Channels [HVA-HVH] High Voltage input channels (see High Voltage Connections)
Digital Inputs [in1-in4] Digital Inputs (see Digital Connections)
Digital Outputs [outA –outD] Digital Outputs (see Digital Connections)
Digital Connections
Four digital inputs and four digital outputs (BNC connectors, TTL-level, (0–0.2 V: low; 2.4–5.5 V: high) allow communication with
external equipment.
The inputs can be connected to interlock switches, sensors or the outputs of other channels. Inputs are pulled high through a 20
KΩ resistor; therefore, when open the TTL input reads high, when short-circuit it to read low. This allows passive testing of input
triggers. If a TTL voltage is applied, the input can be forced high or low.
Outputs might be connected to limit switches, indicator lights, monitoring equipment, alarms, or to the inputs of other channels.

15
Recalibrating the Channels
To ensure the highest accuracy and performance, the HVS448 should occasionally be recalibrated in normal use and must be
recalibrated following a firmware upgrade, which overwrites all the internal calibration data. For operations of low current
where current accuracy is critical, recalibration should be performed before each experiment. For these operations, the HVS448
should be powered up and left on for a minimum of 30 minutes prior to recalibration.
1. Turn off the HVS448 and disconnect everything from the high voltage outputs.
2. Enable the high voltage connections by connecting the supplied 50-Ω terminator to the Interlock Input on the back panel.
3. Connect the HVS448 to your computer and turn on the unit.
Note: For best results, leave the unit on at least 30 minutes before calibration.
4. Run the Sequence software.
5. In Sequence, enter Online mode by clicking the toolbar button.
6. Click the toolbar button to enable high voltage. The “All” indicator on the HVS448 front panel LED should glow green
after a few seconds.
7. In Sequence, choose Actions>Calibration>Recalibrate. As the system recalibrates you will hear a relay clicking inside the
HVS448, and the front panel LEDs will flash red and green.
8. When all the tasks are done, choose Actions>Calibration>Save.The system is now recalibrated and is ready for use.
WARNING: While the HVS is recalibrating the high voltage channels are supplying up to the maximum voltage to
the high voltage connectors. Ensure everything is disconnected from the high voltage connectors
(except for the interlock terminator) on the back panel before performing a recalibration.
Note: If after performing a calibration you wish to return to the previously saved calibration choose Actions>Calibration>
Restore Calibration.

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CHAPTER 4. SEQUENCE SOFTWARE OVERVIEW
Sequence™ software lets you set the HVS448’s high voltage functions. The sourcing and sensing functions can be set manually via
control panels for each channel. The Sequence programming environment lets you create sequences that automatically control
and change the voltage settings. Sequence wizards help simplify the process of defining sequences.
Field Upgradeable Firmware
The HVS448 firmware is field upgradeable. To upgrade the firmware:
1. Download the latest version of Sequence from www.labsmith.com or from a link sent to you by LabSmith.
2. Turn off the HVS448 and disconnect everything from the high voltage outputs.
3. Connect the HVS448 to your computer and turn on the unit.
4. Run the Sequence software.
5. Enter Online mode by clicking the toolbar button.
6. Choose Actions>Update Firmware>Update All. Click OK to continue.
7. The firmware update process takes several minutes. Do not disconnect the power or the serial cable during the update.
8. When all the tasks are done, the system is automatically recalibrated to complete the system upgrade.
9. To verify the firmware version, go to Action>Get Versions. The firmware version number will be displayed in the status
bar. The unit must be Online for the firmware version to be displayed.
Sequence Files
A Sequence file maintains the last manual settings for each channel, as well as all of the programming for a single automated
sequence. Sequence files have a .seq extension.
To open a Sequence file, choose File>Open, then locate the file on your hard drive. You can also choose from recently opened
files at the bottom of the File menu.
When you turn on the HVS448, all of the high voltage channels act as “Inputs;” that is, they float to the driving voltage (if no
external source is supplied, then they will indicate near 0 V). When you open a Sequence file, the channels remain inputs. Click
the Update All button at the bottom of Sequence’s right pane to set all of the channels to the last selected settings.
Online and Offline Operation
Sequence functions in either Onlineor Offline modes. When Online, Sequence communicates with the HVS448, allowing control
and monitoring from a PC. When Offline, Sequence does not communicate with the HVS448, but it does record your settings and
programming which can later be stored in the HVS448.
By default, on startup, Sequence is Offline. Click the toolbar button to switch between Offline and Online modes. The
mode is reported in the status bar at the bottom of Sequence’s main window. When Sequence is instructed to go Online, it
automatically programs the HVS448 with the manual power supply settings.
You can also put the HVS448 Online by going to View>Option>Communications. When the correct serial port is selected the
HVS448 will automatically toggle to Online mode.
Sequence Software Environment
Figure 10 shows the Sequence main window.
This standard Windows interface includes menus and toolbars to access virtually all functions. These options will be discussed
throughout the body of the text. A complete list of menu and toolbar options is also available in Appendix 1.
The left pane lets you navigate through the manual controls for each high voltage channel, as well as through the various parts of
an automated sequence. You can collapse or expand levels to access the settings you need while hiding extraneous functions. To
expand a level, click the “+” button to the left of that item; to collapse a level, click the “–” button.
Click on an item in the left pane to view related settings in the right pane:
-High Voltage Power Supply/Monitor opens the Power Supply Control Panel, an overview of the channels’ manual settings
-Channel A–Hopens the manual settings for a particular channel

17
-Sequencer opens the Sequencer Control Panel, an overview of the current sequence’s settings
-Sequencer A–H opens the sequence for an individual channel
-Step A–Hshows a step within a sequence
-Programmable Trigger Logic lets you define the logic of the signal sent to the digital input.
Figure 10. Sequence Main Window, showing navigation in the left pane and channel settings on the right
Monitor Settings
Monitoring channel measurements and status will help you interpret the state of the HVS channels. Choose
View>Options>Monitoring to control how voltage, current and sequence status will be monitored (Figure 11):
Figure 11. Monitor Settings
-Measurement interval is the frequency with which measurement values are updated in milliseconds. The measurement
interval must be an integer in the range of 1 to 1000000000.The new measurement interval will be applied the next time
Sequence starts. To apply the new measurement interval immediately, select the new interval, click OK, set the software to
monitor None (see Manual Power Supply Control Panel) then reselect the channels to monitor.
-Sampling period is the default period over which measurements are integrated in the HVS. The default period is 25.6 ms;
you can also select a shorter sampling time from the drop-down list.
Note: During high speed measurements the added processing required for monitoring measurements may add jitter to
your timing. Use monitoring thoughtfully if you are performing high-speed or timing sensitive experiments.

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CHAPTER 5. HIGH VOLTAGE POWER SUPPLY: MANUAL MODE
At its heart, the HVS448 is as a multi-channel high voltage power supply. In “manual” mode, you set power supply settings for
each channel through the Sequence software, or through other driver software such as LabVIEW™.
Channel Control Panels
Click on a channel in the left pane of the Sequence window to view its control panel (Figure 12).
Figure 12. Channel A’s High Voltage Control Panel
Note: If the channels are not visible in the left pane, double-click High Voltage Power Supply/Monitor to expand that
section and reveal the eight channels, A–H. Then, click on a channel to display its settings.
Channel Status
Monitoring provides feedback on the channel’s status and measures its present voltage and current values. Click Once to
monitor and report the voltage and current. Select the Monitor check box monitor status and values continuously.
Note:The default monitor setting is governed by the Monitor Settings dialog. To set the default, choose
View>Options>Monitoring (see Monitor Settings).
A channel can monitor either its internally-generated voltage or current, or the voltage/current of an external, connected signal.
When the channel’s setting is Input, the external values will be read. When the channel setting is Voltage Output or Current
Output, the internal values will be measured.
Channel Settings
As mentioned earlier, any channel can:
Function as a high voltage voltmeter with
200 M-Ω input impedance
Select Input to use a channel as a voltmeter for an incoming signal. The
Target Value box will disappear. Click Apply to record the change.
supply voltage while monitoring current
Select Voltage Output, then enter the target voltage to set the channel to
supply a regulated voltage.
supply current while monitoring voltage
Select Current Output, then enter a target current to regulate an output
current.
After selecting the channel function click Apply to initiate the new function.

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Channel Output Limits
To protect external equipment, you can set hard limits for the current and voltage on each channel. Enter lower and upper
Output limits for voltage and/or current.
These limits are particularly useful in automated mode, to ensure that the output voltage/current stays within bounds regardless
of instructions from the sequence. If an out-of-bounds condition occurs, the channel will trip (i.e., will float to the controlling
voltage) or clip (i.e., will be forced within the limit values), depending on the channel’s trip-handling settings (see Error
Reporting/Trip Settings) below.
Note: The HVS448 has an overall maximum output current (value depends on the model, see Table 1). If the total of the
current settings across all channels exceeds this maximum, the overload circuit will trip, and the outputs will
temporarily become inputs (i.e., they float to the driving voltage).
Holdoff value is the duration that the channel must stay beyond the voltage/current limits for the trip settings to take effect.
Error Reporting/Trip Settings
The HVS448 channels continuously check the validity of their settings. In response to invalid conditions, the channels can trip,
clip, or ignore different types of errors. Each channel can have different settings. If Monitoring is turned on for a channel, any
problems on that channel will cause a message to appear in the Errors field.
Click the Trip Setting button to choose the error responses for a channel. The Becomes an Input on dialog box will be displayed
(see Figure 13).
Figure 13. Channel Error Handling Dialog Box
Table 3 describes error messages that may be observed while using the Sequence software.
Table 3. Error Descriptions
Error
Meaning
If box is checked
If box is not
checked
Error Message
Numerical
Exception
Overflow/underflow in a
mathematical calculation (e.g., square
root of a negative number attempted)
Channel becomes an
input (i.e., floats to
driving voltage)
Error is
ignored
“A numerical exception
occurred.”
Current at limit
The current exceeds the channel
limits
Channel becomes an
input
Clip to current
limit
“The current exceeded
the limits.”
Voltage at limit
The voltage exceeds the channel
limits
Channel becomes an
Input
Clip to voltage
limit
“The voltage exceeded
the limits.”
Mismatched
units in
calculations
A mathematical operation was
attempted on numbers with
incompatible units (e.g., voltage
added to time)
Channel becomes an
input
Error is
ignored
“Calculations were
performed on numbers
having inconsistent
units.”
Output setting
beyond limits
The output of the power supply is
exceeded
Channel becomes an
input
Clip to current
or voltage
limit
“The supply was
instructed to regulate
beyond its prescribed
limits.”

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Two other fault conditions are monitored. You don’t have the ability to change these behaviors:
Fault
Meaning
If box is checked
If box is not checked
Error Message
Temperature
limit exceeded
The sensor in the HVS
indicates excessive heat
Channel becomes
an input
Channel becomes an input
(cannot ignore this fault)
“The supply exceeded
its safe operating
temperature.”
Interlock open
(low)
The interlock input is set
to High.
Channel becomes
an input
Channel becomes an input
(cannot ignore this fault)
Manual Power Supply Control Panel
We have just seen that the settings for each channel can be set manually using the individual channel control panels. An
overview of all channels can also be viewed. Click on High Voltage Power Supply/Monitor in the left pane to open the Manual
High-Voltage Power Supply Controls dialog box.
Figure 14. Manual High Voltage Power Supply Control Panel
Overall Settings
At the top of the control panel, set the Output Voltage Range to a value that makes sense for your current experiment. The
voltage and current sliders for each channel will adjust to reflect your choice.
Update All synchronizes the data from all channels, reads the calibration data, updates all channel settings, and updates the
monitored values once for all channels. This function also appears on the Sequencer Control Panel.
Reset All makes all channels inputs, clears all error flags, and stops a sequence if one is running.
Monitoring
Select the Monitor? check box next to each channel to display that channel’s real time Voltage and Current values. You can also
click All to monitor all channels, or None to turn off all monitoring.
Channel Settings
You have the following controls for each channel:
-Click the Input button to use the channel as a voltmeter for an incoming signal. If monitoring is selected, the voltage and
current boxes will show the values of the external signal.
-Click and drag the left slider to set a target voltage for the channel to regulate. As you move the slider, the target
voltage will be displayed. You can also enter the target value in the Voltage box. You will not be able to move the slider
beyond the Voltage Limits for the channel (as set in the Channel Control Panels).