EnerSys Alpha Micro 100, Инструкция по установке и эксплуатации

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017-220-J0 Rev C
Programmable Dry Contact Time of Day Action
You can assign a dedicated timer to a dry contact. Upon entering the Inverter operating mode, the timer is activated
and begins to count down from a user defined value. When the timer reaches zero, the programmed dry contact
relay is activated (Status = ON).
Inverter
mode
entered
Dry contact
activates when timer
counts down to zero
Timer
starts to
count down
Microprocessor



Figure 28 — Programmable Timer Operation
An example of a typical application of this timer-controlled dry contact function is control of a traffic light. When the
grid power fails, the Alpha Micro 100 goes into the Inverter mode and continues supplying backup power to the
traffic light. Since the batteries supplying the backup power have limited capacity, a timer controlled dry contact is
usually configured to switch the traffic light into the flashing amber or flashing red mode after a user-defined period
to conserve battery power.
This setup works for non-rush hour traffic, but during rush hour, it may be desirable to keep the traffic light running
normally as long as backup power is available. To address this issue, a new feature called the
Time of Day Action
has been added to deactivate the timer during a user defined time period up to twice each day.
Microprocessor
Real time clock
Peak period
settings
Disable Timer (Action=ON) or
Enable Timer (Action=OFF)
Inverter
mode
entered

Timer starts to
count down
if enabled

Dry contact activates
when enabled timer
counts down to zero

Figure 29 — Time Of Day Action Operation