4-1. Introduction
This chapter explains how to perform routine maintenance to keep a normally operating
5820A Calibrator in service. These tasks include:
Replacing the fuse
Cleaning the air filter
Cleaning the external surfaces
4-2. Replacing the Line Fuse
The line power fuse is accessible on the rear panel. The fuse rating label above the ac
power input module shows the correct replacement fuse for each line voltage setting.
Table 4-1 lists the fuse part numbers for each line voltage setting.
To check or replace the fuse, refer to Figure 4-1 and proceed as follows:
1. Disconnect line power.
2. The line power fuse and line voltage switch are located in a compartment on the
right end of the ac input module. To open the compartment and remove the fuse,
insert the blade of a standard screwdriver to the left of the tab located at the left side
of the compartment cover.
3. Pry the tab out of the slot and the compartment cover will pop part way out.
4. Remove the compartment cover with your fingers.
5. The fuse comes out with the compartment cover and can be easily replaced.
6. To reinstall the fuse, push the compartment cover back into the compartment until
the tab locks with the ac input module.
Part Number
W109181
W109272
W To ensure safety, use exact replacement fuse only.
Table 4-1. Replacement Fuses
Fuse Description
2A/250V SB (Time Delay)
1A/250V SB (Time Delay)
Maintenance
Introduction
Line Voltage Setting
100 V or 120 V
200 V or 240 V
4
4-3