Glossary of Terms
31
Doc 6001536, Rev C
Glossary of Terms
Address-
Each EMC in a multi-unit configuration must be assigned a unique
number via its Address DIP switch (SW1). Similar to a street
address for homes, the EMC number is the address unit. In the
EMWin, the first EMC is addressed as unit 1.
Diode-
A semi-conductor “one way valve” that is used to protect the EMC
from power transients caused by D.C. operated door strikes or
maglocks. The diode needs to be installed at the strike or maglock.
The diode is polarized, so care must be taken to ensure that it is
installed correctly. Refer to Figure 15 through Figure 17 on pages 18
and 19.
Door Left Open Too Long-
Door is left open beyond the Door Access Time after a valid opening
by card or REX. A Door Status Contact must be installed for
reporting this condition.
Door Forced Open-
Door is illegally opened without card or REX. A Door Status Contact
must be installed for reporting this condition.
Door Status Contact-
Usually a magnetic contact device (N.C.) used to provide the status
of the door (e.g., closed or open).
Normally Open (N.O.)-
A device is considered N.O. if the “normal” condition of the circuit is
not completed or in the “open” state. For N.O. push buttons, pushing
the button completes or “Closes” the circuit. For N.O. Door Strikes,
the N.O. condition will “lock” the door. When the circuit is closed, the
door will unlock.
Normally Closed (N.C.)-
A device is considered N.C. if the “normal” condition of the circuit is
completed or in the “Closed” state. For alarm devices, the “normal”
condition is the completed or closed circuit. When the circuit is open,
it can become an alarm. For N.C. Door Strikes, the N.C. state is that
the strike will remain locked. The lock will unlock in the N.O. state.
PIR- Passive InfraRed detector-
A device to detect body heat and produce a N.O. and/or N.C. output.
Used for automatic exit devices and motion detectors. Requires an
external power source (available in 12 VDC or 24 VDC).
REX- Request to Exit-
A device used to provide exit out of a protected door without causing
an alarm. A REX device for EMC must be a N.O. device.
Transorb-
A device that protects the EMC from power transients potentially
caused by static or some door strikes. The EMC is built with
transorbs for added protection; however, transients from a door
strike need to be stopped at the strike itself. The supplied transorbs
need to be installed at the door strike.
