This part of IEC 61010 specifies safety requirements for HAND-HELD and hand-manipulated
current sensors described below.
These current sensors are for measuring, detecting or injecting current, or indicating current
waveforms on circuits without physically opening the current path of the circuit being
measured. They may be stand-alone current sensors or accessories to other equipment or
parts of combined equipment (see Figure 101). These include measurement circuits which are
part of electrical test and measurement equipment, laboratory equipment, or process control
equipment. The existence of these current sensors and circuits in equipment requires
additional protective means between the current sensor, the circuit and an OPERATOR.
Current sensors require hand manipulation before or after a test or measurement, but do not
necessarily need to be HAND-HELD during the test or measurement.
The following types of current sensors are covered:
a) Type A: a current sensor designed to be applied around or removed from UNINSULATED
HAZARDOUS LIVE conductors. Type A current sensors have defined HAND-HELD or handmanipulated
parts providing protection against electric shock from the conductor being
measured, and also have protection against short-circuits between wires and busbars
during clamping.
b) Type B: a current sensor which has protection against short-circuits between wires or
busbars during clamping but without defined HAND-HELD or hand-manipulated parts which
provide protection against electric shock during clamping. Additional protective means are
necessary to avoid electric shock from HAZARDOUS LIVE conductors which cannot be deenergised
during application or removal of the current sensor.
c) Type C: a current sensor without protection against short-circuits between wires or
busbars during clamping. Type C current sensors are intended to be applied to or removed
from UNINSULATED HAZARDOUS LIVE conductors or from non-limited-energy circuit
conductors only when they are de-energised.
d) Type D: a current sensor designed to be applied around or removed from insulated
conductors or from limited-energy circuit conductors.
A Type D current sensor does not need protection against short-circuits during clamping
and has no defined HAND-HELD or hand-manipulated parts providing protection against
electric shock from the conductor being measured.