Construc Tion; Receivin G, Handlin G And Stora Ge; Periodic C Hecks And Routine Maintenance - GE HGA11A Instructions Manual

The AC voltage or DC current relays are adjusted to pick up at 70-80 percent of
rating at rated frequency.
percent of rating when cold.
*
After AC relays have been continuously energized for a few hours (minimum four
hours) at rated voltage, the pickup and dropout voltages increase by 3. 5 to 7. 5
percent. For DC relays, the pickup and dropout voltages increase by 5 to 10
percent.
The wipe on HGA11 relays exerts a contact pressure of 35 grams
11 a" contacts and 10 grams
*
The HGA11 is a molded case relay.
in Figure 10.
voltage. The function of the voltage barrier is to avoid flashover between a pair
of electrically separate, but mechanically coupled normally closed contacts, or
between a pair of normally open contacts.
against the cover to hold the cover in position.
These relays, when not included as part of a control panel will be shipped in
cartons designed to protect them against damage.
relay, examine it for damage sustained in transit.
handling is evident, file a damage claim at once with the transportation company and
promptly notify the nearest General Electric Apparatus Sales Office.
Reasonable care should be exercised in unpacking the relay in order that none
of the parts are damaged nor the adjustments disturbed.
If the relays are not to be installed immediately, store them in their original
cartons in a place that is free from moisture, dust and metallic chips.
matter that collects on the outside of the case could get inside when the cover is
removed, and cause trouble when operating the relay.
In view of the vital role of relays in the operation of a power system, it is
important that a periodic test program be followed.
checks will vary depending upon environment, type of relay and the user's experience
with periodic testing.
the test interval best suited to his individual requirements, the points listed
under ACCEP TANCE TESTS
* Indicates Revision
The DC voltage relays are adjusted to pick up at 50-60
�
10 percent on 11b" contacts.
The control spring is used for adjusting the pickup and dropout
RECEIVIN G, HANDLIN G AND S TORA G E
P ERIODIC C HECKS AND RO U TINE MAINTENANCE
Until the user has accumulated enough experience to select
should be checked at an interval of from one to two years.
GEH-1793
C ONS TR U CTION
The various parts of the relay can be seen
Cover spring clips maintain spring force
Immediately upon receipt of a
If damage resulting from rough
The interval between periodic
7
�
10 percent on
Foreign