The SKF Electrical Discharge Detector Pen (EDD Pen) is a simple to use hand-held instrument for detecting electrical discharges in electric motor bearings. Electrical discharges are a result of motor shaft voltages discharging to earth through the bearing, causing electrical erosion, lubricant degradation and ultimately bearing failure. 
Electric motors are more vulnerable to suffer electrical erosion in bearings when controlled by a Variable Frequency Drive. When incorporated into a predictive maintenance programme, the EDD Pen can help detect bearings more susceptible to failure, and significantly prevent unplanned machine downtime. 

• Unique remote solution allows operation at a distance from the motors. This helps protect the user from touching machinery in motion
• SKF technology*
• No special training required
• Capable of detecting electrical discharges on a time base of 10 seconds, 30 seconds or indefinite
• LED Backlit screen, allows use in dark environments
• IP 55 can be used in most industrial environments
• Supplied standard with batteries, a spare antenna and language free Instructions for use in a carrying case

Further downloads, documentation available on request
Source: SKF
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