7. The use of the power cam controllers in the electric drives of the deck machinery is restricted to motor ratings of 20 to 25 kW. The factors which impose such restrictions are the operating frequency exceeding 300 operating cycles per hour and the requirements for remote or two-stationed control.
8. For anchor-handling, mooring and similar equipment with rating of up to 20 kW the power cam controllers are the preferred type of controllers.
9. The choice of the power cam controllers for cargo hoisting gear must take into account the required wear resistance of the controller.
10. For devices with a small number of startings and irregular operation controllers may be selected with regard to the starting and rated currents. For highly efficient gear with a number of startings per hour greater than 150 the value of the allowable starting and rated currents must be decreased to 1 or 2 times, so that the v'ear resistance should increase 2.5 or'4 times, respectively.
Hometask: Ex. 35, 36.
The fifth class period
Review of “Ship electrical equipment”. 10
Topical content: Technical documentation of electrical equipment. 8
37 20
Give the exact translation of the Certificate and dwell on it with your fellow-student.
Lloyd’s Register of Shipping Certificate for AC Generator or Motor
Cert. No. Lon. 71083 Works order No. 51433
Main order No. 22/462 21.1.84 Intended for Ship/Yard/Eng.
Type MC 634 В
Date 19.12.84 Port London Manufacturer: Newage Engineers, Limited, Stamford, Lines.
Purchaser: A/S Norsk Elektrisk and Brown Bovery, Oslo, Norway.
Dates of inspection:
First 20.10.84 Last 13.12.84 '
This is to Certify that the >3auxiliary propulsion AC generator/stator, particulars of which are given below, has been inspected by me at the Makers’ works. The construction, workmanship and materials are good, and the machine complies with the relevant of the Society’s Rules.
On completion the >3generator/motor was tested with satisfactory results.
Rating
kVA 560 Volts 380/220 Phase 3
kW 448 Amps 850 Cycles 50
HP — Power factor 0.8 R.P.M. 1,500
Type of enclosure S.P. and D.P. Class of insulation Stator В
Machine No. 51433/1 Date of Rotor F
Temperature test Machine
13.12.84 acting as Generator
| Results of Tests |
|---|
| | | | Generator |
| Duration | 4 Hours | Degrees C. | | Voltage regulation |
| R.P.M. | 1,500 | | | Auto or inherent |
| Volts | 380 | Cooling air 19 | | | |
| Amps | 850 | Stator winding 75.6 | | Full load | No load |
| Power factor 0.8 | Rotor winding 89.7 | R.P.M. | 1,500 | 1,560 |
| | Slip rings — | Volts | 380 | 382 |
| Volts — | | | | |
| Field — | Amps — | | Amps | 880 | — |
| Cycles | 50 | | | | |
Overload test