Omron H8CA-S - Connections; Terminal Arrangements and Power Supply

11
H8CA-S
H8CA-S
Connections
■
Terminal Arrangements
In Counter Function Mode
Note: When the control power supply is DC, terminals ➁ and ➂
are internally connected.
Mode Switch ( ① & ➂ )
When these terminals are short-circuited, set the input and output
modes with the RESET key, not the MODE key.
In Timer Function Mode
Note: When the control power supply is DC, terminals ➁ and ➂
are internally connected.
* Check the operating status of terminals ➂ and ➃ (see table
below) before connecting or disconnecting them.
Timer Control Terminals ➂ & ➃
Be sure these terminals are not connected when using the
H8CA-S as a counter. These terminals are used as shown below
only when H8CA-S functions as a timer.
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Power Supply Connection
Connect power supply across terminals ➁ and ➉ and apply one
of the specified voltages. (Pay special attention to the polarity
when using a DC-operated model.)
! Caution
Do not touch the input terminals while power is supplied to the
H8CA-S or you may experience an electric shock, since this
counter does not have a built-in power transformer. Use of a
model rated at a low DC voltage is recommended when the
counter is installed at a location where the input terminals are
easily accessible.
Note: When connecting external signal input contacts and tran-
sistors, use a power supply having a power transformer
whose primary and secondary circuits are isolated from
each other with the secondary circuit not grounded, for the
input devices, to prevent current feedback and
short-circuiting.
Note: Do not arrange the peripheral circuits of the counter in ei-
ther way, as the internal circuit may be destroyed, render-
ing the counter
unoperational.
To input a signal from a single input contact to several
H8CA-Ss at the same time, be sure to connect the termi-
nals of the same numbers in parallel.
Terminals ➂ & ➃ Operation
Short-circuited Timer operation temporarily interrupted
when power failure accurs in control power
supply
Open Timer operation continues even when
power failure accurs in control power
supply
Reset input
Count input 1 Count input 2
Power
Supply
Reset input Start input
Gate input
Power
Supply
24 to 240 VAC (50/60 Hz)
12 to 120 VDC
(-)
(+)
H8CA-S
Input
terminals
Circuit
Insulated transformer
is necessary
Rectifier
Power supply
Correct:
H8CA-S
Input
terminals
Autotransformer
Grounding
Circuit
Power
supply
Incorrect:
Rectifier