Filament Frequency; Filament Stand-By Circuits; Filament Life; Thermal Or Pressure Switch - Varian B-100 Manual De Instrucciones

C. When this grid voltage is cancelled, the cup becomes the same potential as the filaments and the tube becomes a
conventional X-ray tube. X-rays are produced during the duration of zero grid voltage.
1.9

FILAMENT FREQUENCY

A. Filament frequency limit: 0 – 40 kHz (unless stated differently in the product data sheet for a specific application).
1.10

FILAMENT STAND-BY CIRCUITS

A. During conventional radiographic use, a filament standby circuit may be provided. To prevent filament evaporation,
filament standby should not exceed 2.5 - 2.8 Amps depending on the tube.
1.11

FILAMENT LIFE

A. Excessive boost times must be avoided in all cases and the charts followed closely to avoid shortening useful life. X-ray
tubes used in special applications require lower filament currents to prevent premature filament failure. Review of spe-
cific techniques is required in order to insure the applicable tube will meet the expected filament life. In addition, reduc-
tion of mA values for radiographic techniques with increased peak kV (within limits) can greatly extend the filament life.
1.12

THERMAL OR PRESSURE SWITCH

A. Use of the thermal or pressure switch is mandatory! The thermal or pressure switch does not detect or directly
measure anode target temperature. The switch must be connected as an interlock to prevent exposure and/or provide
a visual or audible warning in an overheated condition.
1.13

FOCAL SPOT MEASUREMENTS

A. Focal spots meet the requirements of IEC 60336.
X-RAY
PRODUCTS
FIGURE 1-2
X-RAY TUBE ASSEMBLY AND
INSTALLATION MANUAL
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