The 4000 Series' voltage and current outputs are protected by Fuses. During the working life of the calibrator, it is possible that at some point these fuses may become damaged by the accidental input of power/current into the calibrator.


A spare set of fuses is provided with each 4000 Series for this event to minimise any downtime.


To access the fuses, the Front Panel of the 4000 Series needs to be removed. Please note that this does NOT affect the warranty or calibration of the instrument.

First, remove the 3 screws holding each handle (total 6 screws) to the front panel assembly


Then, remove the 3 Hexagonal screws on the underside of the front panel




Locate the fuses, which are located on the Connector Board PCB behind the location of the terminals (as looking at the unit from the front, the fuse holders will be on the LEFT of the unit)



The fuses should be replaced with 2A Ultra Rapid type fuses, ensure that the same type of fuse is used to replace the damaged fuses. Fuses can be obtained from Transmille or via the following part numbers : 

Transmille : E035
Farnell / Element 14 : 1354543
RS Components : 420-094


When replacing fuses ensure that the fuse holders are not damaged in any way (i.e. connectors spread apart)