Is there a minimum current and voltage I can set my Monoblock® to? Why?
The current and voltage programming for the Monoblock® should not be set lower than the specified operation range stated in the unit specification. Setting the current and voltage programming below these levels may cause erroneous faults to occur. Spellman High Voltage Monoblocks® have a protection feature that disables the filament output (not including standby preheat current) if the voltage output is below the operating range. This is to protect the filament in the X-ray tube. Because of this feature, there will be zero tube current resulting in an undercurrent fault. Spellman High Voltage Monoblocks® have output voltage regulation fault monitoring and because of the signal-to-noise ratio in the monitoring circuits, operating below a few percent of the maximum rated output may cause a voltage regulation fault. The same situation exists for the current programming setting, which can cause the current regulation fault to trip when operating below a few percent of the rated output. Additionally, on some Monoblocks® the standby preheat current will cause a standby emission current that will prevent normal current regulation to occur below the specified operation range. Attempting to operate below the preheat standby emission current level will result in an overcurrent fault.