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SHAFT HORSE POWER METER (TORSION METER)

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  The Shaft Horse Power Meter measures shaft torque and thrust using strain gauge technology. The instrument consists of an aluminium ring clamped onto the shaft; a stationary unit located next to the shaft and a junction box for the signal and power connections.   The shaft ring contains electronic circuitry for signal processing and transmission, and also serves as protection for the strain gauge(s) which are glued onto the shaft surface. Values for torque and thrust are transferred as frequency modulated signals to the stationary unit through contact free transmission.   Shaft rotation is measured by the sensing of magnets or steel studs on the shaft ring. Shaft power and total energy are calculated by signal processor in the stationary unit. The following propulsion data are recorded by the Shaft Horse Power Sensor and presented on the Display Unit: Rpm, Power, Torque, Thrust, Total Energy, Total revolutions   The Shaft power (Sp) is calculated di...
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Neutral Earthing Resistor (NER) in High Voltage Ships

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 Neutral Earthing Resistor (NER) in High Voltage Ships By Mobin Ahmed ETO, BP Marine Academy, CBD belapur S O L A S R e g u l a t i o n : C h a p t e r I I - 1 , P a r t D - E l e c t r i c a l I n s t a l l a t i o n s . R e g u l a t i o n 4 5 P a r a 4 . 3 . 2 . 1 Introduction Neutral Grounding Resistors are used to reduce problems such as insulation breakdown caused by transient over-voltages produced by arcing ground faults in ungrounded systems and damage to motors and switchgear caused by arcing in solidly grounded systems. The two main methods of system neutral grounding are Low Resistance and High Resistance. Low resistance NER system is not applicable to high voltage ships because the ground fault current is 200A or 400A. This current being of a high value is not safe for equipment and personnel safety. So, only High NER system is used in high voltage ships for the safety of equipment and personnel. The connection of the neutral point of a generator to the ship's hull via...
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HART COMMUNICATION

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    HART Communication By mobin Ahmed ETO, BP marine Academy, CBD Belapur 1. Introduction to HART Communication HART ( Highway Addressable Remote Transducer ) is a widely-used communication protocol in industrial automation that enables digital data to be transmitted along with the traditional 4-20 mA analog signal. This unique setup allows HART-enabled devices to communicate with control and monitoring systems, transmitting additional information such as device diagnostics, status, and configuration parameters in parallel with the primary process variable (like temperature or pressure). This combination of analog and digital transmission means that HART can enhance existing infrastructure by adding digital communication without replacing the analog signal system. As a result, it's compatible with legacy systems and offers easy integration with newer technologies.   2. Hybrid Communication in HART Analog Signal : The conventional 4-20 mA analog signal is t...
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Governor Droop Control

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  GOVERNOR DROOP CONTROL Mobin Ahmed ETO HOD – Electrical, BP Marine Academy   Governor Speed Droop - Speed Droop is a speed control mode of a governor of prime mover driving an alternator connected to bus. This is also known as Governor Droop. Speed droop is a governor function which reduces the governor reference speed as fuel position (load) increases. All engine controls use the principle of droop to provide stable operation. Governor droop allows the engine to run at lower speed when the load increases and at rated speed at no load.   Droop is expressed as a percentage of the original frequency (speed) setting from no load to full load.                              % DROOP = (fNL – fFL) *100/fFL %                    ...
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