Prufrex A 20/21 - electronic anchor controlling device

Stator and anchor test probe PRUFREX A20/A21

The PRUFREX A20 and A21 stator and armature test probes are fully electric test devices for testing direct current, short-circuit and slip ring armatures as well as three-phase stators. The probes can be delivered individually, but are only fully functional with the associated power supply (PRÜFREX NG 20).

Both devices are characterized by the following features:

• Clear PASS/BAD display, visually and acoustically
• Easiest handling as no limit value settings are necessary
• The visual and acoustic display is integrated in a handy device, no additional display devices are required
• The stator and armature can be tested inductively without connecting measuring lines
• Connection to either 230 V or 115 V with PRÜFREX NG20 power supply

Mode of action

The PRUFREX A 20 and PRUFREX A 21 stator and armature testing devices consist of a generator with excitation coil and an indicator coil with evaluation electronics. The excitation coil and indicator coil are combined in the probe head. If the probe head is placed on two adjacent poles parallel to the axis of rotation, the excitation coil generates an alternating magnetic flux. If there is an electrical short circuit in even one turn, this is detected by the evaluation electronics via the indicator coil. The green lamp goes out and the red lamp lights up. When the red lamp lights up, a buzzer sounds at the same time to provide an indication even in unfavorable situations.

 

PRUFREX	A 20	A 21
Distance between the two magnet legs	19 mm	9 mm
Diameter of the probe head	41 mm	26 mm
Required minimum length of the poles of the test object	35 mm	20 mm