Hitachi S-4800 manual Electron Gun, Ion Pump, Other High Voltages, Baking power supply

INTERLOCK
Electron Gun	The Gun cable is now interlocked with a momentary switch.
	If the cover at the top of the electron gun is removed to
	disconnect gun cable, the High Voltage applied to the electron
	gun is shut off. This switch can be overridden for service.
	However, if the cable is replaced the service override is removed.
Ion Pump	The ion pump cover at the back of the electron optical column
	has a safety interlock switch. If the cover is removed, the High
	Voltage supplied to the ion pumps is shut off and lamps in the
	RESET switches for ion pumps located on the evacuation control
	panel will go off. For service the switches can be overridden,
	but as soon as the ion pump cover is put again, the service
	override is removed.
Other High Voltages	High voltage power supply for photo multipliers and electrodes
	are placed inside of a box located at the behind of the specimen
	chamber. The cover of the box has a safety interlock switch. If
	the cover is removed, the High Voltage supplied to the photo
	multipliers and electrodes is shut off. For service the switches
	can be overridden, but as soon as the cover is put again, the
	interlock is functional.
Baking power supply	Baking heater power supply connectors are placed at the right
	side of the ion pumps cover. To connect heater connectors, the
	box cover of the connector must be removed. The box cover of
	the connector has a safety interlock switch. The baking power is
	shut off when the cover is removed. After connecting connectors,
	put the cover again. The baking power then becomes applicable.
Unit power supply	Four side covers of the Main unit have safety interlock switches
	one for each. If one of the side covers is removed, AC power
	supply for the Main unit (for evacuation system, ion pump power
	supply and stage controller) will be shut off. The switches can be
	overridden for service. However, if the covers are put again, the
	service override is removed.
	The interlock location is shown in fig S-6
Protection for Earthquakes	It is recommended that the protection for movement of Main unit
	and Display unit during earthquakes is to be provided by user as
	shown in figures S-7 and S-8.
Gravity location of units	The gravity location of Main and Display unit are shown in fig S-
	9 through S-11.
Water-leakage detection	It is recommended that the water–leakage detector is to be
	provided by user. Figure S-12 shows an example of the water–
	leakage detector.

SAFETY - 17