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Bias voltage for solid-state, charged-particle detectors
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Four supplies, with independently selectable polarity and
voltage from 0 to ±100 V and from 0 to ±1 kV
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Automatic shutdown if the detector current exceeds 20 µA
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Detector protection in case of vacuum failure
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Alarm output for stopping data collection if a detector or
vacuum failure occurs
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LED display for convenient digital readout of the current
or voltage of any supply
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The Model 710 Quad 1-kV Bias
Supply contains four high-voltage power supplies that have independently
selectable output voltages and polarities. Each supply can deliver an output
voltage that is continuously adjustable over the range from 0 to ±100
V or from 0 to ±1 kV, with a maximum output current of 20 µA.
The Model 710 is ideal for providing the bias voltage for solid-state,
charged-particle detectors. It can also be used with ionization chambers
and proportional counters that operate within the range of voltage and
current delivered by the Model 710. |
On each supply, a 10-turn, locking
dial adjusts the output voltage with a control resolution of 0.05% of full
scale. Feedback regulation ensures an output voltage accuracy within ±0.25%
of full scale. The output voltage or output current of any of the four
supplies can be selected for monitoring on the 3-1/2-digit LED display.
This is useful when initially determining the correct bias voltage for
a solid-state detector. Detector bias currents from 0.01 to 19.99 µA
can be measured with a 0.01-µA resolution. |
On each supply, a three-position,
locking toggle switch selects the 1-kV or the 100-V range of output voltage,
or disables operation of that supply. The outputs of all active supplies
are also controlled by the MASTER ON/OFF switch. A red LED on each supply
indicates when its bias voltage is turned on. |
Several features are incorporated
to protect the detectors served by the Model 710, and to ensure the integrity
of the data they are collecting. Green LEDs indicate the polarity of the
output voltage for each supply whenever the bin power is on, and the output
polarity selection jumpers are mounted on the printed circuit board. If
the detector current exceeds 20 µA, the bias voltage for that detector
turns off, and the yellow overload LED turns on to indicate a shutdown
condition. That particular channel remains shut down until the fault is
cleared and the OVERLOAD RESET button is pushed. To protect the detectors
and their associated preamplifiers against discharges in a partial vacuum,
the vacuum shutdown feature can be utilized. A relay closure to ground,
or a low TTL signal from a trip level on a vacuum gauge can be applied
to the VACUUM SHUTDOWN input to turn off all bias supplies in the case
of a vacuum failure in the detector vacuum chamber. A yellow, front-panel
LED turns on to indicate that the vacuum shutdown has been activated. The
rear-panel overload/shutdown alarm output generates a low TTL level whenever
an overload or vacuum shutdown has occurred in the Model 710. This output
can be connected to a computer, or other suitable alarm, to stop the measurement
and prevent the collection of faulty data. The overload/shutdown alarm
outputs from a number of Model 710 modules can be connected together to
generate a common alarm signal. |
The Model 710 contains four identical bias
supplies with independently adjustable voltage and polarity. The specifications
apply to each of the four channels unless noted otherwise. |
PERFORMANCE
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POLARITY Positive or negative polarity,
independently selectable for each channel by printed circuit board jumpers. |
OUTPUT VOLTAGE RANGE Front-panel
switch selectable as 0 to 100 V, or 0 to 1 kV. |
OUTPUT CURRENT RANGE Internally limited
to 20 µA on each output. |
OUTPUT VOLTAGE ACCURACY ±0.25%
of full scale. |
VOLTAGE CONTROL RESOLUTION 0.5 V
on 1000-V range, 0.05 V on the 100-V range. |
OUTPUT VOLTAGE REGULATION <0.001%
or 1 mV (whichever is greater). |
OUTPUT VOLTAGE TEMPERATURE SENSITIVITY
<30 ppm/°C for 0 to 50°C. |
OUTPUT VOLTAGE LONG-TERM INSTABILITY
<0.001%/24 hours. |
OUTPUT RIPPLE <2 mV peak-to-peak,
5 Hz to 100 MHz. |
OUTPUT RISE TIME Nominally 100 ms. |
DISPLAY RANGES 0 to 100 V in 0.1-V
steps on the 100-V range, 0 to 1000 V in 1-V steps on the 1000-V range,
and 0 to 19.99 µA in 0.01-µA steps for current. |
DISPLAY NONLINEARITY £±0.05%
of full scale for voltage from 0 to 100 V or from 0 to 1 kV, and current
from 0 to 10 µA. |
DISPLAY UNCERTAINTY ±1/2 least
significant digit. |
DISPLAY TEMPERATURE SENSITIVITY £50
ppm/°C for 0 to 50°C. |
ELECTRICAL AND MECHANICAL
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POWER REQUIRED The Model 710 derives
its power from a NIM bin supplying ±24 V and ±12 V, such
as the ORTEC Model 4001A/4002A NIM Bin/Power Supply. The power required
is +24 V at 90 mA, +12 V at 390 mA, –12 V at 360 mA, and –24 V at 90 mA. |
WEIGHT
Net 1.4 kg (3.2 lb).
Shipping 2.9 kg (6.4 lb) |
DIMENSIONS Standard double-width
NIM module, 6.90 X 22.13 cm (2.70 X 8.714 in.) front panel per DOE/ER-0457T. |
ORDERING INFORMATION
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To order, specify: |
Model |
Description |
710 |
Quad 1-kV Bias Supply |
C-24-12 |
RG-62A/U 93-W
Cable with two BNC male plugs; 12-ft length |
C-36-12 |
RG-59A/U 75-W
Cable with two SHV female plugs; 12-ft length |
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CONTROLS AND INDICATORS
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MASTER ON/OFF (common to all channels)
Front-panel, two-position, toggle switch enables or disables all four
supplies. |
OVERLOAD RESET (common to all channels)
Front-panel, momentary, push-button switch that clears the overload
shutdown on any channel after a current overload. (See OVL LED.) |
VOLTS/CURRENT (common to all channels)
Front-panel, eight-position, rotary switch selects the parameter to
be read from the display. Either the output voltage or the output current
of each of the four supplies can be selected. |
DISPLAY (common to all channels) Front-panel,
3-1/2-digit, LED display monitors either the voltage or current of the
supply selected by the VOLTS/CURRENT rotary switch. |
POLARITY JUMPER (1 per channel) Internal,
printed circuit board jumper selects either positive or negative output
polarity. |
POS/NEG LEDs (2 per channel) Front-panel,
green LEDs indicate the polarity of the HV OUTPUT. POS is on for positive,
or NEG is on for negative output polarity. |
RANGE (1 per channel) Front-panel,
three-position, locking toggle switch selects a full-range output voltage
of 0 to 100 V or 0 to 1 kV, or disables the output. |
ON LED (1 per channel) Front-panel,
red LED is on if the supply is enabled and has not experienced a vacuum
shutdown or current overload. |
VOLTAGE CONTROL (1 per channel) Front-panel,
10-turn, precision potentiometer with locking, graduated dial provides
a continuously variable output voltage from 0 to 100 V or from 0 to 1 kV,
depending upon the VOLTAGE RANGE setting. (Also see VOLTAGE CONTROL JUMPER.) |
VOLTAGE CONTROL JUMPER (1 per channel)
Internal, printed circuit board jumper selects either the REMOTE INPUT
or the front-panel VOLTAGE CONTROL potentiometer as the source that sets
the output voltage. Normally set to the VOLTAGE CONTROL potentiometer position. |
OVL LED (1 per channel) Front-panel,
yellow LED is on if the supply has been shut down because the current demanded
from the HV OUTPUT exceeded 20 µA. (See OVERLOAD RESET.) |
VACUUM SHUTDOWN LED (common to all channels)
Front-panel, yellow LED is on if a vacuum shutdown has been triggered.
(See VACUUM SHUTDOWN input.) |
INPUTS
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VACUUM SHUTDOWN (common to all channels)
Rear-panel, BNC connector disables all supplies and turns on the VACUUM
SHUTDOWN LED if a low TTL signal or a resistance to ground less than 75
W is applied. The supplies are enabled and the
VACUUM SHUTDOWN LED turns off when a high TTL signal or a resistance to
ground greater than 5 kW is connected to this
input. Used with the trip level on a vacuum gauge to turn off the detector
bias voltage when vacuum is lost in the chamber containing the detectors. |
REMOTE INPUT (1 per channel) Rear-panel,
BNC connector accepts a 0 to +10-V input that controls the output voltage
from 0 to full scale. Active only when the REMOTE INPUT is selected by
the VOLTAGE CONTROL JUMPER. |
OUTPUTS
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HV OUTPUT (1 per channel) Rear-panel,
SHV connector supplies the 0 to ±100 V or 0 to ±1 kV bias
voltage output. |
OVL/SHDN ALARM (common to all channels)
Rear-panel, BNC connector provides an open-collector, active-low, TTL-compatible
signal if a vacuum shutdown or an overcurrent shutdown on any of the four
channels has occurred. An external pull-up resistor to +5 V is required.
OVL/SHDN ALARM outputs from other Model 710 modules can be connected in
parallel to produce a common alarm to signal a detector failure or a vacuum
failure in the experiment. |
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