18
5.5.3
Instrument function:
FunCtion
The BA578E may be configured as a Timer or as a
Clock.
This section of the instruction manual
describes
the
Timer,
for
details
of
Clock
configuration see section 8.
To reveal the existing function of the instrument
select
FunCtion
from the configuration menu and
press
(
. If
ELAP5E
is displayed, the instrument is
already configured as a Timer therefore press
)
to
return to the
FunCtion
prompt in the configuration
menu. If
CloC
is displayed, press the
*
or
&
button to change the setting to
ELAP5E
followed by
the
(
button which will result in a
0000
prompt
being displayed with the first digit flashing. This is a
request for the instruction to be confirmed by
entering
5urE
using the
&
or
*
button to adjust
the flashing digit and the
(
button to move control
to the next digit. When
5urE
has been entered,
pressing
)
will change the instrument to a Timer
and return the instrument to the display mode. To
configure the Timer enter the configuration menu by
pressing the
(
and
)
buttons simultaneously until
function
is displayed.
5.5.4
Input A:
inPut-A
The
inPut-A
function contains two sub-functions
inP . tYPE
which defines the type of sensor that may
be connected to the input and
dEbounCE
which
adjust the amount of input noise rejection.
5.5.5
Input type:
inP
.
tYPE
inP . tYPE
is a sub-menu in the
inPut-A
function
which defines the type of input sensor that may be
connected to input A. To check or change the type
of input, select
inPut-A
in the configuration menu
and press
(
which will reveal the
inP.tYPE
prompt,
pressing
(
again will show the existing input. If set
as required press
)
twice to return to the
configuration menu, or repeatedly press the
*
or
&
button until the required type of input is
displayed, then press
)
twice to return to the
configuration menu.
One of following six types of input may be selected:
Display
Input type
Switching
thresholds
Low
High
oPCoL
Open collector²
2
10k
Ω
VoLt5 L
Voltage pulse low¹
1
3V
VoLt5 H
Voltage pulse high¹
3
10V
CoiL
Magnetic pick-off
0
40mV
Pr
.
dEt
Proximity detector²
1.2
2.1mA
ContACt
Switch contact²
100
1000
Ω
Notes:
1.
Maximum voltage input +30V.
2.
For sensors connected to input A that
require energising i.e. a proximity detector,
a switch contact or an open collector,
terminals 3 & 4 of the BA578E Timer should
be linked together.
3.
To function correctly, the input signal must
fall below the lower switching threshold and
rise above the higher switching threshold.
5.5.6
Debounce:
dEbouncE
dEbouncE
is an adjustable sub-menu in the
inPut-A'
function
which
prevents
the Timer
mis-functioning when the input has noisy edges,
such as those resulting from a mechanical contact
closing and bouncing.
Three levels of protection
may be selected and the amount of debounce
applied depends upon the type of Timer input that
has been selected in the
inP
.
tYPE
function.
The following table shows the minimum time that the
input signal must be continuously above the upper
input switching threshold and continuously below the
lower switching threshold to ensure that the Timer
processes the input signal.
Input switching
thresholds are shown in section 5.5.5.
De-bounce
level
Min input pulse width
Type of Input
Contact
All
others
Default
1600µs
40µs
Heavy
3200µs
350µs
Light
400µs
5µs
5.5.7
Input b:
inPut-b
The i
nput-b
function and sub-functions are identical
to the
input-A
function & sub-functions described in
sections 5.5.4, 5.5.5 and 5.5.6.
Notes:
1.
Maximum voltage input +30V.
2.
For sensors connected to input b that
require energising i.e. a proximity detector,
a switch contact or an open collector,
terminals 7 & 8 of the BA578E Timer should
be linked together.
3.
To function correctly, the input signal must
fall below the lower switching threshold and
rise above the higher switching threshold.
