Technical library

Software download files for SVERKER900

   

 

  

OTS Test Standards

Unbalance phase currents in a power system that exceed the allowable normal operation limit can indicate abnormal condition or even existence of fault(s) in the system. The operating principal unbalance over current protection is normally based on measurement of negative sequence component of unbalance phase currents. Similar to phase over current protection, normally a pick up (start) threshold and a definite time delay for operation can be set.

Directional earth fault protection are commonly used to protect long outgoing feeders from tripping because of fault on other outgoing lines.

A brochure explaining our PowerDB software. This intuitive and robust software interface simplifies the acquisition and management of your test data, giving you control of your Asset Management Process.

Electrical test instrumentation often must operate at medium…or even high…voltages. But even “low” voltage can kill you. What are the guidelines that an operator should consider when selecting and working with instrument test voltages? 

Since there is no such thing as perfect insulation, if any conductor is raised to a potential above that of earth some current is bound to flow to earth from that conductor. The amount of current that flows is dependent on:Voltage on the conductorThe capacitive reactance between the conductor and earthResistance between conductor and earthCurrents that flow to earth are called leakage currents and are usually very small values, typically < 1 mA. However the amount of current that is required to cause distress or harm to a human being or animal is also small, these currents must be limited by circuit design to safe values.If this is not possible, then a 30 mA RCD (residual current device) or 30 mA RCBO (residual current device with overload protection) should be fitted for personal protection.