Sketch 205342 182A787 Figure 1: Schematic Drawing of Magnetic Circuit of Type Figure 2: Internal Schematic of the Type D-3 Relay in the D-3 Relay (Top View). Moving Coil Bearing Sup- Type FT-21 Case. ports, Springs and Contacts Omitted. 3.0 OPERATION...
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0-10 5-0-5 A modification of the D-3 relay, in which a rectifier is 40-80 mounted internally, makes it suitable for ac opera- 100-0-100 tion.
183A344 182A785 Figure 5: External Schematic Diagram for Use of External Figure 6: Internal Schematic of the Type D-3 Relay in the Auxiliary Relay to Prevent Pumping of the Type D- Type FT-21 Case with Self-Contained Auxiliary 3 Relay when used for Overload Protection.
Type D-3 Direct Current Relay 41-151.1H 182A788 182A786 Figure 7: Internal Schematic of the Type D-3 in the Type Figure 8: Internal Schematic of the Type D-3 Relay in the FT-21 Case with Two Self-Contained Auxiliary Type FT-21 Case, Modified for ac Operation.
OPERATION INDICATOR The core and moving coil assembly should not be removed from the frame casting of the D-3 relay The operation indicator (when used) consists of a unless a keeper having the same radius on the core...
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Type D-3 Direct Current Relay 41-151.1H Figure 9: Type D-3 Relay without case. 1- Moving Coil. 2 - Current-carrying restraining springs. 3- Permanent Magnet. 4- Iron-Frame. 5- Scale. 6- Moving Contact. 7- Stationary Contacts.