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Spare parts spare parts, the DCS control system of PLC system and the robot system spare parts,

Brand advantage: Allen Bradley, BentlyNevada, ABB, Emerson Ovation, Honeywell DCS, Rockwell ICS Triplex, FOXBORO, Schneider PLC, GE Fanuc, Motorola, HIMA, TRICONEX, Prosoft etc. Various kinds of imported industrial parts

FI840F 3BDH000033R1 Field bus module

Sensitive earth fault protection for ungrounded systems and systems with Petersen coils (EarthFaultIsol) A. Application The sensitive E/F protection detects E/F's on overhead lines in radial systems. It is suitable for application in ungrounded systems, systems with Petersen coils and in resistance grounded MV and HV systems. The scheme monitors the neutral voltage and current of the protected line. Depending on the characteristic angle chosen, it responds to either the real or apparent value of the neutral power. B. Features
adjustable characteristic angle
compensation of c.t. phase errors
suppression of DC component in voltage and current signals
suppression of harmonics in voltage and current signals. C. Inputs and outputs I. C.t./v.t. inputs
neutral current
neutral voltage II. Binary inputs
blocking signal III. Binary outputs
tripping signal
starting signal IV. Measured variable
zero-sequence power Explanation of the parameters: RunOnCPU defines the processing unit which runs the function. ParSet 4..1 Parameter for determining in which set of parameters a particular function is active (see Section 5.11.). Trip1 01-08 defines the tripping channel activated by the tripping O/P of the function (matrix tripping logic).

Setting: TripAngle

 Phi is evaluated in relation to 'TripAngle' when one of the zones has reached it number of slips, i.e. n
n1 or n2. For a setting of 'TripAngle' = 180°, the tripping command 'Trip1' and the signals 'Trip1' and 'Trip2' are issued immediately. For a setting of 'TripAngle' = 0°, these signals are only issued when the slip detector has reset, i.e. when the generator is again close to synchronism with the power system. A setting of 'TripAngle' between 180° and 0° (typically 90°) determines the rotor angle at which tripping takes place and the signals are given. The setting at which tripping should take place is determined according to an operating point which occurs shortly after the last permissible slip is favourable for the circuit-breaker (least stress due to reignition) Typical setting: 'TripAngle' = 90°. Settings: n1, n2, t-Reset The number of slips n1 or n2 which may be considered permissible depends on the generator being protected and must be stated by the manufacturer. For settings of n1 and n2  1, the reset time 't-Reset' can be set to any low value. For settings of n1 or n2 > 1, 't-Reset' must not be set lower than the period 1/fS of the lowest slip frequency fS to be detected. Slip frequencies from 0.2 Hz upwards are reliably detected using the typical setting of 5 seconds.