Результати проходження тесту
A 5 V DC source has an internal impedance of 0,2 ohms. When a load of 2,3 ohms is applied what voltage will be measured at the source terminals?:
A triac is used to provide temperature control of an oven. The galley complain that the oven only reaches approximately 50 % of demanded temperature. Which of the following is a likely cause?:
Which of the following measures is to be taken when working with batteries?:
Which of the following is an application of a piezoelectric sensor?:
What is the minimum starting requirement of an emergency generator?:
When considering instrumentation systems, what is the meaning of the expression “dead-band”?:
Which of the following is the minimum acceptable value of insulation resistance for High Voltage equipment?:
In tanker operations, there will be some areas and zones where flammable or explosive vapour, gas or dust may be expected. Such areas are classified as hazardous. What is meant by hazardous area Zone 1?:
Which of the following methods may a diode be tested by?:
When performing electrical testing of a three phase motor, insulation resistance measurements may be influenced by which of the following?:
Flow irregularities in pipes are not caused by:
Which of the following is not a mode of a closed loop control?:
A Multimeter is not suitable to measure:
Continuity testing of a delta connected three phase induction motor yields the following results; U1-V1 = 4 ohms, V1-W1 = 4 ohms, W1-U1 = 4 ohms. What is the value of continuity resistance for each winding ie. U1-U2?:
Which of the following functions does the diode shown here perform?:
Which of the following is an application of an capacitive sensor?:
Some ships generate electrical power at 440 Volts, but then step up this voltage to supply specific electrical equipment. One common example, may be to feed a large bow thruster. Why is this done?:
In an automatic temperature control system, operating with a PID controller which of the following settings or parameter adjustments may result in system oscillation?:
What are the main elements for Process Control?:
Following shows circuitry of a peak detector. What is the output voltage curve, Vo if Vi is a sinusoidal input curve?:
When selecting switchgear to work with High Voltage it is important to use an appropriate arc quenching medium. What is meant by arc quenching medium?:
A 250 V contactor has been fitted to a 220 V supply. Which of the following symptoms might be observed?:
The circuit shows a transformer with two windings, N (1) = 2 000 and N (2) = 1 000 turns, on a common magnetic circuit. Assume that there are no energy losses in the transformer itself. Calculate the output voltage V (2) when the input voltage is V (1) = 100 Volt.:
This circuit consists of a current source I, a change-over switch S, a resistor R and a capacitor C. The current/time figures 1 to 4 show possible changes in the current I when the switch S is suddenly shifted from position 1 to 2 at time t = 0. Which diagram is correct?:
Which cell voltage is required to trickle charge a lead acid battery?:
When the cable length exceeds approx. 10 meters we normally have to in case of a Pt 100, in some way compensate for the cable resistance. Do we also have to do this if we choose to use a T802 temperature sensor?:
High Voltage systems rely on the installed protective equipment being able to interrupt any fault in the system. Throughout the system, the fault level has been calculated, and under no circumstances must the system be modified to exceed this fault level. What is meant by fault level?:
The continuity resistance of a 100 m long × 25 sq. mm cable (rated at 100 A) is to be checked. Which of the following results would you anticipate?:
When starting three phase induction motors which of the following starting methods will immediately apply rated voltage to the machine?:
Continuity testing of a delta connected three phase induction motor yields the following results; U-V = 3 Ohms, V-W = 3 Ohms, W-U = 6 Ohms. Which of the following is the likely condition?:
What is the advantage of a transmitter with a narrow measurement range?:
How can a lead-acid type battery be checked to confirm if it is fully charged or not?:
When polarity of the incoming power line is reversed, what happens to the DC motor?:
This circuit consists of a voltage source V, a change-over switch S, a resistor R and a capacitor C. The voltage/time figures 1 to 4 show changes in the voltage V(C) when the switch S is suddenly shifted from position 1 to 2 at time t = 0. Only one of the diagrams is correct. Which?:
This figure shows a transformer, with two windings, N(1) = 2 000 and N(2) = 1 000 turns, on a common magnetic circuit. Assume that there is no energy loss in the transformer itself. Calculate the current l(2) when the current l(1) = 2 A.:
What should be the healthy continuity resistance of a 220 V, 2,2 kW, 10 A heating element, when checked near to it’s rated operating temperature?:
Which electronic component or system is this graphical symbol illustrating?:
Can a ZENER BARRIER be installed in a hazardous area?:
When there is a need to interrupt current flow in a high voltage system it may be very difficult to quench the electrical arc which is generated at the circuit breaker contacts. Which of the following arcing media is commonly found in high voltage marine switchgear?:
The circuit shows a full-wave bridge rectifier. Which electronic component should be connected between “a” and “b” in order to obtain reduced ripple voltage to the load RL.: