This series of bench power supplies offer high power outputs (in excess of 350 Watts) in a casing
which is both compact and lightweight when compared with conventional designs. Their high
performance is derived from a r egulator design which combines switch-mode and linear
techniques to achieve high efficiency with excellent regulation, transient r espons e and very low
noise.
The supplies feature high accuracy voltage and current metering on bright 0.5" LEDs,
overvoltage and thermal protection, and remote sense t er m inals. The output operates in
constant voltage or constant current mode with automatic cross over and mode indicat ion.
Coarse and fine controls permit the out put voltage t o be set within 10 mV and the current limit
control is logarithmic to give good res olution at low current settings.
The supplies have a robust steel case which is half-rack width (3U height). They are Saf et y
Class I, Installation Category II instruments which meet EN61010-1 s afety requirements and
comply with EN61326-1 EMC standard.
2
Output Voltage Setting:
By coarse and fine controls; 10mV setting r esolut ion.
Sensing:
Remote via rear panel screw terminals or direct via shorting strip ( supplied) .
>5kΩ in constant current mode (voltage limit at max.).
Temperature Coefficient:
Typically <100 ppm/°C.
Meter Resolution:
10mV, 10mA
Environmental:
Indoor use at altitudes up to 2000m, Pollution Degr ee 2.
Specification
OUTPUT SPECIFICATIONS
Voltage Range: Nominally 0-35V (35V/10A), Nomin a lly 0-18V ( 18V/ 20A)
Current Range: Nominally 0-10A (35V/10A), Nominally 0-20A (18V/20A)
Output Current Setting: By single semi-logarithmic control; 10mA setting resolution.
Output Mode: Constant voltage or constant current with automatic crossover.
Output Switch: Electronic. Preset voltage and current displayed when off.
Output Terminals: 4mm terminals on front panel, scr ew term inals at r ear.
Output Impedance:
Output Protection: Forward protection by Over-Voltage-Protection (OVP) trip; maximum voltage
OVP Range: 10% to 110% of maximum output voltage set by fr ont panel screwdriver
OVP Delay: <200µs
Load & Line Regulation: <0.01% of maximum output for 90% load change or 10% line change.
Ripple & Noise: <1mV rms typical in constant voltage
HF Common Mode
Noise:
Transient Response: 20µs to within 50mV of setting for a 5% to 95% load change.
Protection Functions: Overvoltage trip. Regulator overtemperatur e. Sense m iswiring.
Status Indication: Output off lamp. Constant voltage mode lamp
<1mΩ in constant voltage mode.
that should be applied to the terminals is 50V.
Reverse protection by diode clamp for reverse currents up to 3A.
adjustment.
<3mA rms typical in constant current.
Typically <3mV rms, <10mV peak.
Constant current mode lamp. Trip message on display.
METER SPECIFICATIONS
Meter Types: Dual 4 digit meter s with 12.5m m ( 0.5") LEDs. Reading rate 4Hz.
Meter Accuracy: Voltage 0.2% of reading ± 1 digit, current 0.5% of reading ± 1 digit.
GENERAL
AC Input Voltage: 110V-120V AC or 220V-240V AC ± 10%, 50/60Hz. Installation Category II.
Power Consumption: 600VA max.
Operating Range: 5°C to +40°C, 20% to 80% RH.
Storage Range: –40°C to +70°C.
Size: 210 x 140 x 385mm (W x H x D), half rack width x 3U height
(optional rack mounting k it available)
Weight: 5kg.
Safety & EMC: Complies with EN61010-1 & EN61326-1.
For details, request the EU Declaration of Conformity for this instrument via
This power supply is a Safety Class I instrument according t o I EC classification and has been
designed to meet the requirem ents of EN61010-1 (Safety Requirements for Electr ical Eq uipm ent
for Measurement, Control and Laborator y Use). It is an Installation Category II instrument
intended for operation fr om a nor m al single phase supply.
This instrument has been tested in accordanc e with EN61010-1 and has been supplied in a safe
condition. This instruction manual contains some information and warnings which have to be
followed by the user to ensure safe operation and to r etain the inst r um ent in a safe condition.
This instrument has been designed f or indoor use in a Pollution Degree 2 environment in the
temperature range 5°C t o 40°C, 20% - 80% RH (non-condensing). It may occasionally be
subjected to temperatures bet ween +5°C and –10°C without deg r adation of its safety. Do not
operate while condensation is present.
Use of this instrument in a manner not spec ified by these instructions may impair the safety
protection provided. Do not operate the instrum ent outside its rat ed supply voltages or
environmental range.
WARNING! THIS INSTRUMENT MUST BE EARTHED
Any interruption of the mains earth conduct or inside or outside t he inst r um ent will make the
instrument dangerous. Int ent ional inter ruption is prohibited. The protective action must not be
negated by the use of an extension cord without a protective conductor.
When the instrument is connected to its supply, terminals may be live and opening the covers or
removal of parts (except those to which access can be gained by hand) is likely to expose live
parts. The apparatus shall be disconnected from all voltage sources before it is opened for any
adjustment, replacement, m aint enance or repair. Capacitors inside the power supply may still be
charged even if the power supply has been disconnected from all voltage sources but will be
safely discharged about 10 minutes after s witching off power.
Any adjustment, maintenance and repair of the opened instrument under voltage shall be
avoided as far as possible and, if inevitable, shall be carried out only by a skilled person who is
aware of the hazard involved.
If the instrument is clearly defective, has been subject to mechanical damage, excessive
moisture or chemical corrosion the safety protection may be impaired and the apparatus should
be withdrawn from use and returned for checking and repair.
Make sure that only fuses with the required rated c ur r ent and of the specified type are used for
replacement. The use of makeshift fuses and the short-circuiting of fuse holders is prohibited. Do
not wet the instrument when cleaning it.
The following symbols are used on the instrument and in this m anual:-
Earth (ground) terminal.
mains supply OFF.
mains supply ON.
alternating current (ac)
direct current (dc)
4
Mains Operating Voltage
Check that the instrument oper at ing voltage marked on the rear panel is suitable for the local
supply. Should it be necessary to change the operating voltage, proceed as follows:
1. Ensure that the instrument is disconnected from the AC supply.
2. Remove the 6 screws holding the case upper and lift off the cover.
3. Change the appropriate zero-ohm links beside the t r ans former on the pcb:
Link LK5 only for 230V operation
Link LK1 and LK3 only for 115V operation
Installation
4. Re-assemble in the reverse order.
5. To comply with safet y standard requirements the operating voltage on the rear panel must be
changed to clearly show the new voltage setting.
Mains Lead
When a three core mains lead with bare ends is provided this should be connected as follows:
GREEN/YELLOW - EARTH
Safety Earth Symbol
When f it t ing a fused plug a 5 amp fuse should be fit t ed inside t he plug . As the colours of the
wires in the mains lead of this apparatus may not correspond with the coloured markings
identifying the terminals in your plug proceed as follows:
The wire which is coloured green-and-yellow must be connected to the terminal in the plug which
is marked by the letter E or by the safety earth symbol shown above or coloured green or greenand-yellow.
The wire which is coloured blue must be connected to the terminal which is marked with the letter
N or coloured black.
The wire which is coloured brown must be connected to the terminal which is marked with the
letter L or coloured red.
BROWN - MAINS LIVE
BLUE - MAINS NEUTRAL
WARNING! THIS APPARATUS MUST BE EARTHED.
Any interruption of the protective conductor inside or outside the apparatus or disconnec t ion of
the protective earth terminal is likely to mak e t he apparat us dangerous. Intentional interruption is
prohibited.
5
Output Setting
With the PO WER switch on (l) and the OUTPUT push-button switch off ( out ) the output voltage
and current limit can be accurately set using the t hree output controls; the left-hand meter
indicates set voltage and the right-hand meter set current.
When the OUTPUT is switched on, the ON LED and the CV (constant voltage) LED will light; the
left-hand meter continues to s how the set voltage but the right-hand meter now shows actual
current drawn. Alternate presses of the I METER DAMPING button will switch current meter
damping in and out; with damping switched in the DAMPED LED will be lit and the average value
of a varying load current will be read.
If the output goes int o cur r ent limit the CI (constant current) LED will light instead of the CV LED
and the left-hand meter will now show the actual voltage at the output terminals; the r ight-hand
meter will continue to show the set current limit.
At any time, the set voltage and set current levels can be reviewed by pressing the CHECK V /I
button.
Outputs from several supplies may be connected in series or parallel to produce hig her voltages
or higher currents respectively. Care must be taken when connecting supplies in series to ensure
that the maximum voltage rating of any output terminal (300V peak maximum with respect to true
ground) is not exceeded.
Operation
Connection to the Load
Connection to the front panel output term inals c an be m ade with 4mm plugs, spade terminals or
wire ends. To minimise voltage drop, the connecting leads to the load should be of an adequate
wire gauge and be kept short. Load wires should also be twisted tog et her t o minimise
inductance.
To overcome er r or s introduced by connecting lead resistance at higher currents the remote
sensing facility should be used (10 mΩ of lead resistance will drop 0.2 Volt at 20 Amps). Remove
the two shorting links made between the rear output and sens e t er minals and connect the sense
terminals directly to the load; the power connections may be made f r om eit her the front or the
rear terminals.
To ensure good coupling between the output and sense, the sense wires should be twisted with
their corresponding output leads bef ore the output leads are twisted together.
The voltage drop in each output lead must not exceed 1 Volt.
The shorting links should be re-m ade bet ween the rear sens e and out put terminals when remote
sensing is not being used. However, the sense connection is also made internally through a low
value resistor and only a small error between the set and actual voltage will result if the links are
left disconnected.
The output is fully floating and eit her t er m inal can be connec t ed t o ground or raised by up to
300V peak above true ground; however, such voltages are hazardous and great care should be
taken.
6
The current limit control can be set t o lim it the continuous output current to levels down to 10mA.
However, in common with all precision bench power supplies, a capacitor is connected across
the output to maintain stability and good transient response. This capacitor char ges to the output
voltage, and short circuiting of t he out put will produce a short cur r ent pulse as the capacitor
discharges which is independent of the current limit s et t ing.
Protection
Overvoltage protection (OVP) is fully variable within the range 10% to 110% of the supply's
maximum output level. The OVP limit is set via the screwdriver adjustable SET OVP preset
potentiometer, accessible through a hole in the front panel. Rotating the preset clockwise
increases the limit, which can be read directly on the left-hand display by pressing the READ
OVP button. If the voltage on the output exceeds the set O VP for any reason, including an
externally forced voltage, the output will be tripped off.
The output will also be tripped off if the therm al sens ing detects overheating of any of the power
semiconductors, or if the sens e wires are wired to the wrong out put or if an attempt is made to
draw power from the sense wires.
In all the above cases, the 'TRIP' message will be shown in both displays. Once the cause of the
trip has been removed, normal operation can be restor ed by switching the PO WER switch off
(
) then on (l) again.
The output is protected f r om r everse voltages by a diode; the continuous reverse current must
not exceed 3 Amps, although transients can be much higher.
Ventilation
These instruments are very efficient but nevertheless can g ener ate significant heat at full power.
The supplies rely on convection cooling only and it is therefore important that ventilation is never
restricted if perf ormance and safety are to be maintained. If the supplies ar e m ount ed in a
restricted space, eg. a 19 inch rack , then adequate ventilation must be ensured by using, for
example, a fan tray.
Fuse
Maintenance and Repair
The Manufacturers or their ag ents overseas will provide repair for any unit developing a f ault .
Where owners wish to undertake t heir own maintenance work , this should only be done by skilled
personnel in conjunction with the service manual which may be purchased directly from the
Manufacturers or their agents overseas.
The correct fuse type for all models and AC supply ranges is:
10 Amp 250V HBC time-lag, 5 x 20 mm
Make sure that only fuses with the required rated current and of the specified type are used for
replacement. The use of makeshift fuses and the short-circuiting of fuse-holders is prohibited.
To replace t he fuse, first disconnect the instrum ent from the AC supply. Remove the 6 cover
securing screws and lift off the cover. Replace the fuse with one of the correct t ype and refit the
cover.
Note that the main function of the fuse is to make the instrum ent s afe and limit damage in the
event of failure of one of the switching devices. If a fuse fails it is t her efore very likely that the
replacement will also blow, because the supply has developed a fault; in such circumstances the
instrument will need to be returned to t he m anufacturer for service.
Cleaning
If the PSU requires cleaning use a clot h t hat is only lightly dampened with water or a mild
detergent. Polish the display window with a soft dry cloth.
WARNING! TO AVOID ELECTRIC SHOCK, OR DAMAGE TO THE PSU, NEVER ALLOW
WATER TO GET INSIDE THE CASE. TO AVOID DAMAGE TO THE CASE OR DISPLAY
WINDOW NEVER CLEAN WITH SOLVENTS.
7
Loading...
+ 18 hidden pages
You need points to download manuals.
1 point = 1 manual.
You can buy points or you can get point for every manual you upload.