Spellman uX50P50, Instruction Manual

uX MANUAL 

8 

118151-001  REV A 

FILAMENT LIMIT: 

The maximum current that the 

filament power supply can operate is user adjustable from 
1.0A to 3.5A. The Limit adjustment is made when the 
power supply is in the high voltage OFF mode (Interlock 
Open) via the screwdriver adjustable potentiometer 
labeled “FIL I LIM ADJ” that is accessible through the top 
cover.  

A test point is provided on pin 9 on the 15 pin D connector 
for monitoring the Filament Limit set point. The test point 
scaling is 1VDC = 1amp.  See Figure 3.3 for the 
recommended interface circuit.  

Due to the wide variety of X-ray tubes available, uX 
power supplies are shipped with the Filament Limit set for 
minimum. The operator must set filament limit at the time 
of installation in accordance with the X-ray tube 
manufacturers recommendations. 

FILAMENT PREHEAT:  

uX filament power supplies 

operate at a user selectable preheat current level whenever 

the +24VDC input power is applied to the unit and the 
Interlock is Open (High Voltage OFF).  The Preheat Level 
is adjustable from between .8A to 2.5A. 
Selecting the correct preheat current level can greatly 
reduce or eliminate the overshoot that typically occurs on 
the output emission current when operating into a “cold 
filament”. 
The Preheat adjustment is made when the power supply is 
in the high voltage OFF mode (Interlock Open) via the 
screwdriver adjustable potentiometer labeled “PH ADJ” 
that is accessible through the top cover.  

A test point is provided on pin 14 on the 15 pin D 
connector for monitoring the Filament Preheat set point. 
The test point scaling is 1VDC = 1ADC. See Figure 3.3 
for the recommended interface circuit.  

Due to the wide variety of X-ray tubes available, uX 
power supplies are shipped with the Filament Preheat set 
for minimum. The operator must set filament Preheat at 
the time of installation

.

Figure 3.1 Typical Operating Setup uX

GND

+24V

DANGER

DANGER

AGAINST RISK OF FIRE

FOR CONTINUED PROTECTION

TYPE AND RATING FUSE.

REPLACE ONLY WITH SAME

mA ADJ

HV ON

kV ADJ

FIL I LIM ADJ

POWER ON

FIL OUT

FIL RET

I/O

FILAMENT

X-RAY TUBE

ANODE