THE P R O F E S S I O N A L SIDE
MODEL M A 2 8 5 0
MODEL M A 6 5 A MODEL M A 6 4 0
R U G G E D · ACCURATE · TUBELESS
MAGNETIC AMPLIFIER DC SOURCES 'MA-NOBATRONS*/
Sorensen MA-NOBATRONS* have been designed for industrial applications a n d unattended installations where the utmost in maintenance-free service is required. NEW
IMPROVED
MODEL M A 6 5 A INPUT
SPECIFICATIONS M O D E L M A 640
1 0 5 - 1 2 5 V A C , 1 0 , 6 0 cycles
M O D E L M A 2850 190-230VAC, 30, 6 0 cycles 4-wire wye.
OUTPUT
6VDC,edj. ± 1 0 %
L O A D RANGE
0-5 amperes
REGULATION
± 0 . 2 % against line or load 0.1 5 seconds under worst conditions
RECOVERY TIME
4 . 5 - 7 . 7 V D C , adj.
2 3 - 3 2 V D C , adj.
0-40 amperes
0-50 amperes
± 1 . 0 % lor any combination of line or load 0.2 seconds under worst conditions
0.5 seconds under worst conditions
Conracr your local Sorensen representative, or write for further information. If you hove special requirements in magnetic amplifier DC sources, write or call the Applications Engineering Department, and your problem will receive prompt attention. SORENSEN & C O M P A N Y , I N C . •*en. U.S. Pot. Oft.
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3 7 5 FAIRFIELD AVE., STAMFORD, C O N N .
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INDUSTRIAL AND ENGINEERING CHEMISTRY
work in engineering is related to the work of the marketing and financial sections of his company Personal attitudes permeate the entire work atmosphere of an engineer and have a profound effect on the way he approaches his work and the results he obtains. A few of the attitudes which he should cultivate are a positive outlook, an open mind, constructive discontent, selfconfidence, and the courage of his own convictions. For some reason we live in a highly conservative world where the first reaction to a new idea is inevitably, "What's wrong with it?" or " W h y won't it work?" If he is ever to make substantial creative contributions, the engineer must learn to approach new ideas positively, with the attitude of "What can I do with this to make it work?" or "What is good about this idea that I can use in another way?" Closely associated with the positive approach is the attitude of the open mind or willingness to give new ideas adequate consideration and a fair try. If Fulton, Edison, and the Wright brothers had listened to others' opinions of their great inventions we would probably not have those inventions today. The world is not much less conservative today than it was in their time. It would pay today's engineer to remember that, if engineers were infallible interpreters of physical laws and effects, we would need far fewer engineers. Until wc are this good we can't afford to close the door on any idea whether it is proposed by ourselves or others. In the current world and national atmosphere it is clear that he who is not making progress is falling behind. Consequently an attitude of constructive discontent is a highly desirable attribute. The engineer must be convinced that there is always a better way, and he should take as a personal challenge the implication that any product or process has been completely optimized. A constant search for new and better products and ways of doing things is essential to our personal, business, national, and global well being. Perhaps the most important and effective attitude that can be carried into engineering work is that of selfconfidence in one's own ability. Most engineers do not realize their
