Q Bank & Answer - Electrical Engineer - ERRU

01. Voltage regulation of alternator with ERRU for all capacities of alternator. [ c]

 a)+/-5% 

b)+/-3% 

c)+/-2% 

d) None

Answer - c)+/-2% 

02. Voltage ripples of output supply with ERRU should be less than [ a ]

a)2% 

b)5% 

c)15%

 d)none

Answer -  a)2% 

03. ISO pack power diode modulars are used for converting [ a ]

a)AC to DC 

b) DC to AC

 c) both A&B 

d) none

Answer - a)AC to DC 

 

04. The advantage of ISO pack power modules are [ d ]

a) Directly can mount on heat sink

b) two diode combined unit

c) Small in size

 d) all of the above

Answer -  d) all of the above

05. The ERRU shall have the following protection [ d ]

 a) Over voltage/surge protection

 b) DC output short circuit protection

 c) Over charging current limit protection 

d) all of the above

Answer -   d) all of the above

06. UVC used in ERRU must be [ a ]

a) Suitable to work with all capacities 

b) suitable to work all makes

c) Both A&B 

d) none

Answer -   a) Suitable to work with all capacities 

07. The over voltage setting of OVP with ERRU should be set at [ a ]

 a)140-145V 

b)125-130V 

c)135-140V 

d)none

Answer -   a)140-145V 

08. The battery charging current limit with 4.5 KW ERRU is to be set at [ a ]

 a) 24A +/-2A 

b)12A +/-2A 

c)36A +/-2A 

d) none

Answer -  a) 24A +/-2A 

09. The battery charging current limit with 25kw ERRU when both alternators are paralleled is to be set at [ a ]

a) 110A +/-5A 

b)220A +/-5A 

c)220A +/-10A 

d)none

Answer - a) 110A +/-5A 

10. OVP provided with ERRU shall latch before output voltage reaches to [ c ]

 a) 145V 

b) 150V 

c) 135V+/-2V 

d) none

Answer -  c) 135V+/-2V 

11. Hall senses are used to sense [ c ]

a) Total alternator load current 

b) battery charging current

c) both A&B

 d) none

Answer -  c) both A&B

12. OVP is provided in ERRU for the purpose of [ c ]

a) To arrest the over voltage

b) latch the output voltage 90V for working lights and fans

c) Both A&B

d) none

Answer -  c) Both A&B

13. PWM stands for [ a ]

 a) Pulse width modulation 

b) phase width modulation

 c) both A&B 

d) none 

Answer -  a) Pulse width modulation 

14. EEPROM stands for [ a ]

a) Electrically erasable programmable read only memory

b) Electronically erasable programmable read only memory

c) Both A&B 

d) none

Answer - a) Electrically erasable programmable read only memory

15. SMPS stands for [ a ]

a) switch mode power supply 

b) single mode power supply

c) sweep mode power supply 

d) none

Answer - a) switch mode power supply 

16. IGBT stands for [ a ]

a) Insulated gate bipolar transistor 

b) isolated gate bipolar transistor

c) Both A&B 

d) none 

Answer -  a) Insulated gate bipolar transistor