BEKA BA577E, Manual

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1. DESCRIPTION
The BA577E is a general purpose, panel mounting
instrument with a single input that can be configured
as a Timer or as a Clock. As a Timer the BA577E is
able to measure and display the elapsed time
between external events, or control external events
via two optional factory fitted control outputs.
When configured as a Clock, the instrument can
display time in a variety of formats and the two
optional control outputs may be configured to switch
loads
on and off at pre-set times.
This instruction manual is divided into sections.
Common features
2. System design
3. Installations
4. Accessories
Timer
5. Operation as a timer
6. Configuration example
7. Maintenance
Clock
8. Operation as a clock
9. Configuration example
10. Maintenance
This instruction manual supplements the
abbreviated instruction sheet supplied with each
instrument.
2. SYSTEM DESIGN
Fig 1 illustrates the basic circuit that is used for all
BA577E Timer installations. Clock installations are
the same, except that the input terminals 5 & 6 are
not used. For simplicity the optional control outputs
are described separately in section 2.4 of this
manual.
Fig 1 BA577E connection
2.1 Power supply
The BA577E requires a supply of 10 to 30V dc
between terminal 1 & 2 and consumes:
10mA without optional backlight
plus 22mA with optional backlight
plus 6mA when terminals 3 & 4 are linked
2.2 Sensor input
As shown in Fig 1 the BA577E Timer can be
controlled by a wide range of sensors, the BA577E
input is not used when the instrument is configured
as a Clock.
The following table shows the instrument's input
switching thresholds when configured to operate
with various sensors.
For reliable operation the
BA577E input must fall below the lower threshold
and rise above the upper threshold.
Sensor
Switching thresholds
Lower Upper
Voltage pulse low 1.0V 3.0V
Voltage pulse high 3.0V 10.0V
Magnetic pick-off 0 40mV peak
Proximity detector 1.2mA 2.1mA
Switch
100

1000

Open collector
2k

10k
