THURLBY THANDAR INSTRUMENTS
QL Series II
Precision linear dc power supplies - single and triple outputs
unrivalled accuracy, resolution, stability and noise performance
advanced user interface gives superior control
GPIB, RS-232, USB and LAN interfaces; LXI class C compliance
aimtti.com
multiple output ranges provide greater flexibility
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Linear regulation with more than 100 watts per output
Advanced dc power supply range, single or triple output
Very high precision, very low noise, excellent dynamics
Advanced user interface with numeric and rotary control
Multiple voltage/current ranges for increased flexibility
Multiple non-volatile memories for power supply set-ups
Switchable remote sense provides perfect load regulation
Comprehensive protection including OVP and OCP trips
Compact bench footprint; modular width for rack mounting
Auxiliary output fully variable 1.00V to 6.00V at 3A
with selectable voltage and current metering (T models)
Bus programmable via USB, RS232, GPIB or LAN (P models)
LAN interface is LXI class C compliant
Duplicate power and sense terminals at rear (P models)
Building upon success
The original QL series re-defined the laboratory power supply in terms of
precision and performance.
Now the QL Series II builds upon that success and adds new features and
models.
One third or two third
rack width, 4U height
Linked mode control for
tracking operation or
series/parallel wiring
Up to 160 memory stores
for voltage and current
settings
Variable over-voltage and
over-current protection
trips
Safety binding post terminals
can accept fixed-shroud 4mm plugs** as
well as normal plugs, bare wires, and fork
connectors
16-bit precision, 1mV
setting resolution
Current resolution down
to 0.1mA
Individual output switches
plus master control
Remote or local sense with
keypad selection
Auxiliary output, fully variable 1.00V to 6.00V
at 3A (bus control and readback on P versions)
Rotary control of voltage
and current
Watts display
(V x A)
Exceptional precision
The QL series offers an unparalleled level of precision. Voltage and current are
controlled using instrumentation quality 16 bit DACs enabling voltages to be set
to 1mV resolution even at full output voltage.
Indeed, the accuracy is sufficient for the QL to be used as a calibration source for
some hand-held DMMs.
Multiple ranges for greater flexibility
The QL series II provides multiple ranges for increased current capability at
lower voltages. The QL564, for example, is a 112W PSU with three ranges.
The main range offers 0 to 56 volts at up to 2 amps. The higher current range
provides up to 4 amps for voltages up to 25V. A further low current range
provides an enhanced current setting and measurement resolution of 0.1mA.
Unrivalled performance
The QL series uses pure linear technology and offers unrivalled performance in
terms of regulation, output noise and dynamics.
Line and load regulation are close to the limit of measurement. Recovery time
from transient current pulses is better than 50µs.
Differential output noise is less than 350µV rms in CV mode and down to
20µA rms in CI mode.
Of equal importance for critical applications in areas such as telecoms is
common mode noise current (the noise current flowing between the output
terminals and ground). This is only ??µA rms on the QL - dramatically better
than most other PSUs.
Fully bus programmable via USB, RS232,
GPIB or LAN interfaces (P versions)
Multiple ranges for
increased flexibility
Duplicate rear terminals
(P versions)
Direct numeric setting
of voltage or current
Exceptional facilities and performance
Fast, simple and safe to use
The user interface of the QL series has been painstakingly designed to provide
rapid control whilst guarding against any possibility of error.
Unlike other digitally controlled units, the QL series provides both numeric and
rotary control.
Illuminated keys and display legends provide instant confirmation of settings
and status.
Voltage and current setting can be performed in either of two ways:
Direct numeric entry
Settings can be made by direct numeric entry using the 0 to 9 keypad.
Each new setting is previewed on the display and must be confirmed with the
OK key.
Settings recalled from memory are similarly previewed and confirmed.
Numeric setting is very fast requiring only three key presses to set to 5 volts,
for example, (V, 5, OK).
To set a more precise level such as 12.725 volts requires more key presses, but
can still be done in seconds.
Incremental rotary control
For those preferring quasi-analogue control, or for applications where the
voltage or current must be gradually changed, the Jog wheel is available. The
wheel has a positive stepped action but can be spun rapidly when required.
Output voltage can be incremented or decremented in steps of 0.1V, 10mV or
1mV. Current steps can be selected from 0.1A down to 0.1mA.
The Jog function can be left permanently engaged or can be disabled at the
touch of a button.
Instant Limits view
To enable the current limit to be set before connecting the load, the limit
setting is displayed when the output is set to Off.
Pressing the Limits key at any time provides a temporary display of the limit
values allowing precise adjustment to be made.
Setting memories for added convenience
The QL Series II provided storage of up to 50 power supply sets-up in non-
volatile memory (160 set-ups for a triple). Voltage, current, OVP and OCP are
all saved.
An further power-down memory is also incorporated. Upon mains switch-off,
the set-up of the PSU is saved and is automatically restored at switch-on.
On the triple output models, independent memories are provided for each
output, plus an additional set for ‘linked’ mode where the user may wish to
recall settings for both outputs simultaneously.
Remote or local sense
The QL series provides full remote sense capability via dedicated sense
terminals. Remote sense is essential to maintain regulation at the load (two
0.01 Ohm connection leads will drop 100mV at 5 amps).
When remote sense is not required, internal local sensing can be selected at
the touch of a button.
Further facilities - triple output models
These triple output models have two main outputs plus one auxiliary output.
The casing is twice the width of a single output model (two-thirds rack).
Linked mode convenience
The triple output models have two identical outputs which are both
independent and isolated.
Illuminated keys selects which output is to be adjusted and provide
unambiguous indication.
In situations where the user wishes to set similar voltages or currents on both
outputs, “linked” mode is available. When linked, all adjustments are applied
to both outputs simultaneously.
Linked mode can provide tracking outputs
and is particularly useful when the user
wishes to wire the outputs in series or
parallel to obtain higher voltages or
currents. A “copy” function allows all of
the settings of one output to be duplicated
on the other prior to linking.
For even greater flexibility, the outputs can be linked when set to different
voltages or currents allowing separate settings to be loaded into the linked-
mode memories for simultaneous recall.
Auxiliary output for low voltage circuits
The triple output models incorporate a third “auxiliary” output intended for
powering logic and other low voltage circuitry.
This output is fully isolated from the main outputs and provides a fully variable
voltage of between 1.00 and 6.00 volts at a current of up to 3 amps.
Voltage and current can be read on the main display at the touch of a button.
An independent output on/off switch is provided.
On P versions, voltage and on/off status are bus controllable, and output
current and status can be read-back.
Comprehensive output control
Each output has its own illuminated dc on/off key providing completely
independent control.
For situations where power needs to be
connected or disconnected from all three
outputs together, master on/off keys are
also provided.
OVP and OCP trips with “alarm” output
The QL series provides fully adjustable over-voltage and over-current trips.
These trips can be used both as a fail-safe against accidental mis-setting and
as a protection against inappropriate load conditions.
In addition to turning the output off, a trip condition switches the rear panel
alarm signal enabling other equipment to be controlled.
For complete protection of the power supply, the trip will also be operated by
over-temperature, or excess voltage on the sense terminals.
Instant watts display
The product of voltage and current can be displayed at any time by pressing
the V x A button.
The power is displayed with a resolution down to 1 milliwatt.
Safety binding-post terminals
All QL series power supplies are fitted with the new TTi designed output
terminals. As well as acting as conventional binding posts for bare wires,
spade connectors, or standard 4mm plugs, these can accept a 4mm safety
plug with rigid insulating sleeve,
a requirement specified by an
increasing number of laboratories
for safety reasons.
Limited opening length combined
with raised insulated shoulders also
make these terminals “touch proof”
for voltages up to 250V.
Bench and System use
The QL-P models include all of the manual control features of the standard models plus comprehensive
digital interfaces and rear terminals.
All power supply settings can be controlled via the bus. Voltage and current can be set to a resolution
of 1mV or 0.1mA for each main output, and to 10mV for the auxiliary output.
Actual voltage and current can be read back along with the power supply status.
Rear output terminals
Power and sense terminals are duplicated on the rear panel for rack mount applications or other
situations where rear connection is more appropriate.
Digital remote control
To meet the varying needs of today’s engineers, a comprehensive array of interfaces is provided.
RS-232, USB, GPIB and LAN (Ethernet) with LXI support are provided as standard. Each of the digital
bus interfaces provides full control of voltage, current, and output on/off, plus read-back of voltage,
current and status. The interfaces are at ground potential and are opto-isolated from the output
terminals.
GPIB
The GPIB interface is compliant with IEEE-488.1 and IEEE-488.2. Currently GPIB remains the most
widely used interface for system applications.
RS-232
An RS-232/RS-423 interface is provided for use with legacy systems. This type of serial interface
remains in common useage and is perfectly satisfactory for the control of power supplies because
data speed is not an issue.
USB
USB provides a simple and convenient means of connection to a PC and is particularly appropriate for small system use. A USB driver is provided which supports
Windows 2000, XP , Vista and Windows 7. Further versions will be supported as they are released.
LAN (Ethernet)
The LAN interface uses a standard 10/100 base-T Ethernet hardware connection with ICMP and TCP/IP Protocol for connection to a Local Area Network or direct
connection to a single PC. This interface supports LXI and is highly appropriate for system use because of its scalable nature and low cost interconnection.
LXI Compliance
The LAN interface is compliant with LXI-C. LXI (LAN eXtensions for Instrumentation) is the next-generation, LAN-based modular architecture standard for
automated test systems managed by the LXI Consortium, and is expected to become the successor to GPIB in many systems. For more information on LXI and
how it replaces GPIB, or operates along side it, go to: www.tti-test.com/go/lxi
IVI Driver
An IVI driver for Windows is included. This provides support for common high-level applications such as LabView*, LabWindows*, and HP/Agilent VEE*.
Compact design for bench or rack
The QL series are highly compact with a small footprint for bench use. Fold-away feet are incorporated which can be used to angle the front panel upwards.
Single output models are one-third rack width, whilst triple output models are two thirds rack width.
A universal rack mount tray is available which will mount one, two or three singles, one triple, or one triple plus one single.
On P versions, rear output terminals are provided for system use.
Comprehensive Remote Control (QL-P)
Model Table
Model O/Ps Main Output(s) Aux Output Max. Power Interfaces Terminals Input V/A Size W x H x D (mm)* Weight (kg)
QL355 1 0 - 35V/0 - 3A or 0 - 15V/0 - 5A - 105W - Front only 250 max. 140 x 160 x 290 5.4
QL564 1 0 - 56V/0 - 2A or 0 - 25V/0 - 4A - 112W - Front only 250 max. 140 x 160 x 290 5.4
QL355T 3 2 x 0 - 35V/0 - 3A or 0 - 15V/0 - 5A 1 - 6V/3A 228W - Front only 500 max. 280 x 160 x 290 10.5
QL564T 3 2 x 0 - 56V/0 - 2A or 0 - 25V/0 - 4A 1 - 6V/3A 242W - Front only 500 max. 280 x 160 x 290 10.5
QL355P 1 0 - 35V/0 - 3A or 0 - 15V/0 - 5A - 105W RS232/USB/GPIB/LAN Front/Rear 250 max. 140 x 160 x 290 5.5
QL564P 1 0 - 56V/0 - 2A or 0 - 25V/0 - 4A - 112W RS232/USB/GPIB/LAN Front/Rear 250 max. 140 x 160 x 290 5.5
QL355TP 3 2 x 0 - 35V/0 - 3A or 0 - 15V/0 - 5A 1 - 6V/3A 228W RS232/USB/GPIB/LAN Front/Rear 500 max. 280 x 160 x 290 10.6
QL564TP 3 2 x 0 - 56V/0 - 2A or 0 - 25V/0 - 4A 1 - 6V/3A 242W RS232/USB/GPIB/LAN Front/Rear 500 max. 280 x 160 x 290 10.6
* Dimensions exclude feet and terminals. Single output models are 1/3rd rack x 4U. triple ouput models are 2/3rd rack x 4U.
Technical Specifications
MAIN OUTPUT(S)
QL355, QL355P, QL355T, QL355TP
Max. Output Power: 105 watts
Output Ranges: Range 1 - 0 to 35V, 0 to 3A
Range 2 - 0 to 15V, 0 to 5A
Range 3 - 0 to 35V, 0 to 500.0mA
QL564, QL564P, QL564T, QL564TP
Max. Output Power: 112 watts
Output Ranges: Range 1 - 0 to 56V, 0 to 2A
Range 2 - 0 to 25V, 0 to 4A
Range 3 - 0 to 56V, 0 to 500.0mA
All Models
Voltage Setting: By floating point numeric entry or rotary jog wheel; resolution 1mV.
Current Setting: By floating point numeric entry or rotary jog wheel; resolution 1mA or
0.1mA depending on range.
Setting Accuracy: Voltage - 0.03% ±5mV. Current 0.2% ±5mA/0.5mA
Output Mode: Operation in constant voltage or constant current modes with
automatic cross-over and mode indication by LEDs.
DC Output Switch: Sets output voltage and current levels to zero when Off.
Output Terminals: 4mm safety binding post terminals on 19mm (0.75”) spacing.
Duplicated on rear terminal block (P versions only)
Load Regulation: For any load change, at the output terminals, using remote sense.
Voltage <0·01% + 2mV.
Current <0·01% + 250µA; <0.01% +50µA on 500mA range.
Add typically 2·5mV for a 0·5V drop in the positive output lead.
Line Regulation: Voltage <0·01% + 2mV for 10% line change.
Current <0·01% + 250µA; <0.01%+ 50µA on 500mA range
Ripple and Noise: Typically <0.35mV rms CV mode, and <0.2mA rms CI mode
(<20µA rms on 500mA range)
Transient Response: <20usec to within 15mV of setting for 90% load change
Temperature Coeff.: <(50ppm+0.5mV)/ oC (voltage), <(100ppm+1mA/0.1mA)/oC (current)
Remote Sense: Eliminates up to 0.5V drop per lead. Remote sense operation selected
from front panel and indicated by LED
Sense Terminals: Recessed sprung sockets for direct insertion of wires
Duplicated on rear terminal block (P versions only)
OUTPUT PROTECTION
Output Protection: Output will withstand forward voltages of up to 20V above rated
output voltage. Reverse protection by diode clamp for currents
up to 3A.
Fault Condition Trip: The output will be shut down if any of the four trip conditions listed
below occur. In addition to the output being set to Off, an isolated
rear panel signal is also activated.
Over Voltage (OVP): Settable 1V to 40V (QL355) or 60V (QL564) in 0.1V steps
Over Current (OCP): Settable 0.1A to 5.5A (QL355) or 4.5A (QL564) in 0.01A steps
Over Temperature: Monitors internal temperature rise to protect against excess ambient
temperature or blocked ventilation slots.
Sense Error: Monitors the voltage between the remote sense terminals and output
terminals to protect against mis-wiring.
Trip Output Signal: Isolated open-collector output signal on rear panel.
METERING
Display Type: Dual digital displays per output using 14mm (0.56”) high brightness
LEDs. 5 digits for voltage, 4 digits for current.
Update rate 4 per second.
Meter Function: Voltage meter shows set voltage when in CV mode and measured
voltage when in CI mode.
Current meter shows measured current when in CV mode and
set current when in CI mode.
Limits Display: With the dc output switch set to Off, both meters show the set values
(i.e. the limits). With the output On, either the voltage meter or
current meter will show a measured value (depending on the CV/CI
mode). Pressing the Limits button will provide a temporary display
of the set values.
Watts (VxA) Display: The voltage meter can be made to show the instantaneous calculated
product of voltage and current.
Meter Resolution: Voltage: 1mV (CV mode) or 10mV (CI mode)
Current: 1mA or 0.1mA depending on range
Power: 0.01W or 0.001W depending on range
Meter Accuracy: Voltage: 0.1% of reading ±10 mV (CI mode)
Current: 0.2% of reading ± 0.005A or 0.5mA (CV mode)
Power: 0.3% of reading ± 0.05W or 0.005W
SETTINGS MEMORIES
Main Output(s): Up to 50 set-ups per output can be saved and recalled via the
keyboard or remote interfaces.
Parameters Stored: Range, Set volts, Set current, OVP, OCP.
Recall system: Settings are previewed onto the displays before being actioned.
Linked Mode: On triple output models when in Linked mode, a further set of 50
memories stores and recalls values for both outputs simultaneously.
Auxiliary Output: Up to 10 voltage settings can be saved and recalled via the keyboard
or remote interfaces.
ALARM OUTPUT
Isolated rear-panel open-collector output signal. User can select output to be activated for
either OVP, OCP, Overtemperature or Sense miswiring, or for any of those four faults.
LINK & COPY - Triple Output Models
Each output can be controlled independently or can be linked. When linked, keyboard and jog
wheel control operates on both outputs simultaneously.
Linked mode can be used to create tracking outputs, or for convenient series or parallel
operation of the two outputs.
A Copy function is available which copies all of the settings for output 1 to output 2 (Range,
Set volts, Set current, OVP, OCP).
Linked mode can also be used to store the settings for both outputs to a group of common
memory stores when simultaneous recall is required.
(Note: Linked mode can be selected with differing voltage and current settings on the two
outputs. However both outputs must be set to the same range.)
AUXILIARY OUTPUT - Triple Output Models
Output Voltage: 1.00 to 6.00V
Output Current: >3.0 A maximum. LED indication of over-current.
DC Output Switch: Sets output voltage level to zero when Off.
Setting Accuracy: ±0.5% ±10mV
Ripple and Noise: <2mV rms, 10mVp-p
Load Regulation: < 1% for 90% load change.
Line Regulation: < 0.1% for 10% line change.
Meter Accuracy: Voltage ±0.5% ±10mV, Resolution 10mV
Current ±0.5% ±10mA, Resolution 10mA
Output Protection: Output will withstand up to 16 V forward voltage. Diode clamped for
reverse voltages and 1 Amps reverse current.
Output Terminals: 4mm safety binding post terminals on 19mm (0.75”) spacing.
Duplicate screwless terminals at rear (P versions only)
DIGITAL BUS INTERFACES (P suffix versions only)
Full remote control and read-back using RS-232, USB, GPIB or LAN (compliant with LXI class
C). All interfaces are at ground potential and opto-isolated from the output terminals.
RS-232
Standard 9-pin D connector. Baud rate variable 600 to 19,200.
USB
USB 2.0 connection (backwards compatible with USB 1.x). Operates as a virtual COM port.
GPIB (IEEE-488)
The interface conforms with IEEE-488.1 and IEEE-488.2.
Ethernet (LAN)
Standard 10/100 base-T hardware connection. ICMP and TCP/IP Protocol for connection to
Local Area Network or direct connection to a single PC.
LXI Compliance
LAN interface is compliant with LXI class C. (LXI is the abbreviation for Lan eXtensions for
Instrumentation). For more information visit: www.tti-test.com/go/lxi
DRIVER SOFTWARE SUPPLIED (P versions only)
IVI Driver
An IVI driver for Windows is supplied. This provides support for common applications such as
LabView*, LabWindows*, HPVEE* etc.
USB Driver
An installation file is supplied which calls a standard Windows* USB driver.
* LabView and LabWindows are trademarks of National Instruments.
HPVEE (now Agilent VEE) is a trademark of Agilent Technologies.
* USB interface is supported for Windows 2000, XP, Vista and Windows 7. Further versions will be
supported as they are released.
Windows is a trademark of Microsoft.
Designed and built in Europe by:
Thurlby Thandar Instruments Ltd.
Glebe Road, Huntingdon, Cambridgeshire. PE29 7DR United Kingdom
Tel: +44 1480 412451 Fax: +44 1480 450409
Email: sales@tti-test.com Web: www.tti-test.com
Brochure Part No. 82100-1190 Iss. 2
Specifications (Continued)
DIGITAL PROGRAMMING PERFORMANCE (P versions only)
Voltage Setting - Main Output(s)
Resolution/Accuracy: 1mV / ± (0.03% +5mV)
Current Setting - Main Output(s)
Resolution/Accuracy: 0.1mA / ± (0.2% +5mA) or 0.01mA / ± (0.2% +0.5mA) on 500mA range
Voltage Setting - Auxiliary Output (Triple Output Models)
Resolution/Accuracy: 10mV / ± (0.5% +10mV)
Programming Speed
Command Delay: Typically <25ms (this must be added to any of the figures below)
Voltage Up Time: <10ms* to 1%
Voltage Down Time: <40ms* to 1% (full load); <0.6s* to 1% (no load)
* The up and down times vary with range and voltage step size. More information is
contained in the operating manual which can be downloaded from our web site.
KEYBOARD & ROTARY CONTROL
All functions, including the selection and set-up of the remote control interfaces, can be set
from the keyboard. The rotary jog control can be used to adjust output voltage and current
settings in a quasi-analogue mode.
GENERAL SPECIFICATIONS
Input
AC Input: 230V AC or 115V AC ± 10%, 50/60HzInstallation Category II.
Input Power: Single - 250VA max., Triple - 500VA max.
Temperature & Environmental
Operating Range: +5ºC to +40ºC, 20% to 80% RH
Storage Range: -40ºC to + 70ºC
Environmental: Indoor use at altitudes up to 2000m, Pollution Degree 2.
Cooling: Intelligent variable-speed fan. Over-temperature trip shuts down
output if internal temperatures exceed predetermined thresholds..
Safety & EMC
Safety: Complies with EN61010-1
EMC: Complies with EN61326
Physical
Size: Single - 140 x 160 (1/3 rack, 4U) x 290mm
Triple - 280 x 160 (2/3 rack, 4U) x 290mm
(size excludes feet, knobs and terminals).
Weight: Single - 5.5kg (12lb), Triple - 10.5kg (23lb)
OPTIONS
Rack Mount
RM410 19 inch 4U mount for up to three single output units or one triple plus one single.
Blanking plates are supplied for unused sections.
Accuracy specifications apply for the temperature range 18
o
C to 28
o
C after one hour warm-up.
Thurlby Thandar Instruments Ltd. operate s a policy of continuous development and reserves the
right to alter specifications without prior notice.
Other TTi Power Supply Series
EL-R series
Compact linear regulated power supply series with analog controls. Single,
dual and triple outputs. 30 to 130 watts
PL & PL-P series
Advanced linear regulated power supply series with analog controls
combined with digital functions. Ultra compact. Single and dual outputs.
75 to 180 watts.
Models with RS-232, USB, LAN, and optional GPIB (PL-P).
PLH & PLH-P series
Higher voltage versions of the New PL and PL-P series offering output
voltages up to 250V. Single output, 90 watts.
Models with RS-232, USB, LAN and optional GPIB (PLH-P)..
EX-R series
Compact mixed-mode regulated power supply series with analog controls.
Single, dual and triple outputs. 175 to 420 watts.
TSX & TSX-P series
High performance mixed-mode regulated single output power supply series
with analog or digital controls. 360 watts.
RS-232 and GPIB controlled models (TSX-P).
CPX series
Compact ‘PowerFlex’ regulated series, single and dual output with analog
controls. 350 to 840 watts.
Models with RS-232, USB, GPIB and LAN interfaces (CPX-P).
QPX series
High power PowerFlex and PowerFlex+ regulated units, digital controls.
Single and dual outputs, 1200 watts.
Analog, RS-232, USB, GPIB & LAN (LXI) interfaces (QPX-P).
