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556-P and 556H-P High-Voltage Power Supply

The Models 556-P and 556H-P High-Voltage Power Supplies provide the noise-free, well-regulated, very stable high voltage necessary for proper operation of photomultipliers, ionization chambers, semiconductor detectors, electron multipliers, and many other devices. The Model 556-P is housed in a double-width NIM module (per DOE/ER-0457T). The Model 556H-P is a stand-alone instrument designed for bench-top operation.  The low-noise output is continuously adjustable from ±10 to ±3000 V dc with 0 to 10 mA load current. Noise on the output is <10 mV peak-topeak, thereby ensuring the highest performance in high resolution, semiconductor or scintillation spectroscopy systems. 

The front-panel digital meter allows visual monitoring of either the output voltage or the output current. 

The output voltage can be controlled from ±10 to ±3000 V by application of an external input voltage of 0 to ±6.9 V dc. This feature is desirable for control applications and is standard on all units. 

The input power for Models 556-P and 556H-P is taken directly from the ac line, either 115 or 230 V ac, 47 to 63 Hz. 

Overload and short-circuit protection networks permit operation into short circuits without damage to the instrument. 
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  • Specifications +

    OUTPUT POLARITY Positive or negative, selected by switch on rear panel.
    OUTPUT RANGE 50 to 3000 V; minimum usable voltage 10 V.
    REGULATION ≤0.0025% variation in output voltage for combined line and load variations within operating range at constant ambient temperature.
    TEMPERATURE INSTABILITY <±50 ppm/ºC after 30-minute warmup; operating range 0 to 50ºC.
    LONG-TERM DRIFT <0.01%/hour and <0.03%/24-hour variation in output voltage at constant input line voltage, load, and ambient temperature after 30-minute warmup.
    OUTPUT RIPPLE <15 mV peak-to-peak, 20 Hz to 20 MHz.
    OVERLOAD PROTECTION Internal circuitry protects against overloads including short circuits.
    RESETTABILITY Output voltage can be reset to within 0.1%.
    POWER Front-panel toggle switch energizes unit when power cord is connected to appropriate source, and an adjacent red LED lamp indicates when power is applied.
    OUTPUT VOLTAGE One 6-position switch, one 5-position switch, and one 10-turn precision potentiometer; output voltage is the sume of the 3 settings.
    METER Front-panel toggle switch selects display of output voltage in V or load current in mA.
    POLARITY Rear-panel switch selects either positive or negative output polarity.
    CONTROL Rear-panel locking toggle switch selects the reference source for the output voltage.
    INT Selects the internal reference source; the front-panel controls select the output voltage. 
    EXT Selects the external reference source; output voltage is proportional to magnitude of reference output.
    AC VOLTAGE Rear-panel slide switch selects either 115 V or 230 V ac input voltage.
    AC POWER 103-129 V or 206-258 V, 47-63 Hz, 70 W nominal at full output power; supplied through international standard IEC power connector on rear panel.  Fuse rating: 1.5 A,  250 V fuse for 115 V ac operation or 0.75 A, 250 V fuse for 230 V ac operation.
    EXTERNAL CONTROL Full range of output voltage can be bases on an external dc reference level furnished through a rear-panel BNC connector; control voltage polarity must be the same polarity as that selected by the rear-panel polarity switch; this input protected against over-voltages >±7 V.  Input impedance >45 kΩ.
    REGULATED DC OUTPUT The adjusted and regulated voltage, with selected polarity, is furnished simultaneously to the two SHV connectors on the rear panel.
    METER Front-panel LCD display indicates output voltage in kV ±10 V or load current in mA ±10 µA.  Load current is sum of external load current and internal load current.  Internal load resistance is -5 MΩ.
    POWER REQUIREMENTS 115 or 230 V ac, 47-63 Hz, 70 W nominally at maximum output load.
    WEIGHT Net            556-P      3.6 kg (8.0 lb).
                     556H-P    5.7 kg (12.6 lb).
    Shipping     556-P      4.5 kg (10.0 lb).
                     556H-P    6.6 kg (14.6 lb).
    DIMENSIONS 556-P   Standard double-width NIM module, 6.90 X 22.13 cm (2.70 X
                8.714 in.).
    556H-P  11.43 X 22.35 X 29.21 cm (4.5 x 8.8 x 11.5 in. )

    To order, specify:
    Model Description 
    556-P High-Voltage Power Supply
    556H-P High-Voltage Power Supply