Spellman X3645, Instruction Manual

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DF/FF MANUAL 118002-001 R
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1 INTRODUCTION
1.1 DESCRIPTION OF THE
DF/FF SERIES
This series of high voltage power
supplies represents a radically new
advanced approach to X-ray generator
power requirements. These power
supplies provide all of the power,
control, and support functions required
for practically all X-ray diffraction
(XRD) or X-ray fluorescence (XRF)
applications. The DF/FF series provides
high voltage, high current outputs with
very low ripple. Extremely stable
voltage and current outputs result in
significant performance improvements
over previously available technology.
Low output ripple provides higher
intensity levels, with no increase in tube
loading.
All of these advancements are possible
only by Spellman’s long history in X-
ray power systems. This series of power
supplies utilizes extremely advanced
quasi-resonant PWM conversion
techniques, along with sophisticated
digital technology.
The DF series is specifically designed
for XRD X-ray tube applications. The
high voltage is a negative polarity, and
the filament circuits are referenced to
the cathode high voltage potential,
(floating filament). The FF series is
specifically designed for XRF X-ray
tube applications. The high voltage is a
positive polarity, and the filament
circuits are referenced to cathode
ground potential, (grounded filament).
The X-ray tube voltage, tube emission
current, tube filament current limit, and
maximum tube power, are all
continuously adjustable via analog
remote controls or digitally over RS-232
interface (optional).
The power supplies operate from a
variety of line voltages and are fan-
cooled, requiring no water-cooling.
Custom designed units for single use or
OEM applications are available.
1.2 STANDARD FEATURES
The DF/FF series incorporates extensive
standard features designed to optimize
user control and safety.
KV AND MA/FILAMENT CURRENT
RAMP CIRCUITS:
This feature
provides for a gradual rise for kV, mA,
and filament current. This feature is
designed to limit voltage shock and
filament shock to the X-ray tube. The kV
ramp rate is approximately 30 seconds.
The filament current is slowly increased
until the desired mA level is achieved.
This time is typically 30 seconds for full
mA output. These ramp conditions are
started at the initial X-RAY ON control
signal or when the kV control, (front
panel potentiometer or remote
programming), drops below the kV MIN
level. The kV MIN level is typically set at
8kV. The kV MIN level is adjustable by
an internal resistor valve. Other kV MIN
levels can be accommodated. Consult
Spellman Engineering for further
information.
FAIL-SAFE, DUAL INDICATOR
LAMPS:
The X-ray on lamp utilizes a
sensing circuitry for detecting proper
operation of the lamp for the indicator. If
the X-ray on lamp is not functioning, the
power supply will not generate high
voltage. If the X-ray on lamp is depressed
and the indicators do not illuminate, the