Datasheet

www.elma.com Elmaset C | 3_13
C
3: Handles
Hot-Swap Safely at the Touch of a Button
Modern backplanes are equipped with high pin density connectors. In order to manage the occurring high connecting forces, up to 500
N (100lbs.) for a 6U plug-in unit, a new insertion/extraction handle was designed and standardized in IEEE 1101.10.
The standards for CompactPCI Hot Swap and VME64x show new features added to the IEEE handle. To meet these different demands,
Elma has developed two handles.
To confirm with IEEE 1101.10 and CompactPCI without Hot Swap or other applications where high insertion/extraction forces have to be
managed, Elma developed a handle with an optimised ratio of leverage that impairs minimum vertical forces to the rack. Thus preventing
the front extrusions from buckling which can cause malfunction of the handle. In addition the Elma handle has a positioning pin. This pin,
anchored in the tapped strip, precisely aligns each board within its slot, eliminating lateral forces to adjacent boards (this guarantees the
functionality of the EMC gaskets and reinforces the front extrusions). A matter of course are the coding (up to 4096 possibilities) and the
ESD pin for electrostatic discharge of the front panel (via an ESD clip in the card guide) as defined in the IEEE standard.
The CompactPCI Hot Swap specification asks for a switch incorporated in the handle assembly. And the VME64x specifications requires a
handle with a build in locking feature. Elma has added these features to the above mentioned handle. Thus offering the user two almost
identical handles for different requirements. Unique and user friendly is the locking feature:
To remove the plug-in unit first the handle has to be unlocked by pushing down the red button on the handle. The red button also acti-
vates at the same time the switch (open). The red button remains depressed. Now the plug-in unit can be removed by pushing the handle
outwards. If the red button was pushed in error, push the handle inwards. When the plug-in unit is fully seated, the red button jumps up
automatically thus locking the handle and activating the switch (closed).
To separate the two operations (unlocking and extraction) means security and guarantees that the handle meets completely the Hot Swap
specification. According to the specification the switch has to change the state as the handle is unlocked but before any movement of
the board begins. On insertion the switch should change state after the board is fully seated (physical connection is done). This locking
happens automatically with the Elma handle. Only when the plug-in unit is fully and correctly inserted, will the handle be locked and the
switch actuated (closed).
The Hot Swap specification highly recommends a protective cover for Hot Swap boards. The cover from Elma can be mounted with-
out screws. It is inserted between printed board and front panel. Then the double-sided adhesive tape is pressed on the printed board
through the pins of the connector. No time or money is wasted fitting screws and in addition the cover can be fixed on all 6 U-, 160 mm
and 80 mm boards even on those where holes for a protective cover are missing.
Handle in closed (locked) position