Positron Teleline 751109/15, Описание и установка

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Power Alarm Contact Features and Specification
3.7 Power Alarm Contact Features and Specification
The shelf offers the means of monitoring the output of Model 751313MC,
751318MC and 751319MC Plug-in Power Supplies using dry alarm contacts.
The Violet/Slate and Slate/Violet wires of the Station cable provide Normally Open
(NO) contacts during normal operation. If the output of an internal plug-in power
disappears, either through an AC or DC primary source power outage, an input
fuse failure, a power supply failure or a power short-circuit in the shelf, the alarm
contacts will close to enable a current, AC or DC, to circulate in the alarm circuit.
If the shelf contains a battery backup, the shelf will remain operational and the
alarm contact closure can be used to trigger notification of a service requirement.
This prevents a service outage by enabling the servicing of the shelf before the
batteries discharge.
If the shelf contains two redundant power supplies, one unit would generate an
alarm closure to signify loss of output, while the redundant power supply takes
over the powering of the shelf. This enables a service call without a service
outage.
The alarm contacts are rated for voltages of up to 125 Vac or 30 Vdc and currents
up to 150 mA (AC or DC).
There are many applications for use of dry alarm contacts, such as:
Q
closing a circuit to turn on a 12 Vdc light indicator
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using the contact closure to drive a higher current relay that could turn ON a
light bulb or a horn alarm
Q
closing a circuit to drive a Piezo alarm sounder
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provide contact closure for an input of alarm monitoring/reporting units
This feature is especially useful for installations with critical circuits that cannot
tolerate a service outage or where downtime must be minimized.