Technical data

146 U1401A User’s and Service Guide
8 Specifications
Measurement Category
The U1401A is intended to be used for measurement under
Measurement Category II, 150 V for altitude up to 2000 m.
Measurement category definitions
Measurement CAT I Measurements performed on circuits that are not directly
connected to MAINS.
For example, measurements on circuits that are not
derived from MAINS, and specifically protected (internal)
mains- derived circuits.
Measurement CAT II Measurements performed on circuits that are directly
connected to the low voltage installation.
For example, measurements on household appliances,
portable tools, and similar equipment.
Measurement CAT III Measurements performed in fixed building installation.
For example, measurements on distribution boards, circuit
breakers, wiring (including cables), bus bars, junction
boxes, switches, socket outlets in fixed installation,
equipment for industrial use, and stationary motors with
permanent connections to fixed installation.
Measurement CAT IV Measurements performed at the source of the low voltage
installation.
For example, electricity meters, measurements on primary
overcurrent protection devices, and ripple control units.