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16
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2) Connections
Turn off the power supply and buffer relay power supply before connections to prevent an electric shock.
(1) Connect cables to the load via a buffer relay.
(2) Use cables with the crimp style terminals with insulation sleeves for the alarm output terminals.
(3) If a voltage of more than 30 VAC or 60 VDC is to be applied to the output terminals, use type O
crimp style terminals with insulation sleeves. Furthermore, use double-insulated wires (dielectric
strength of 2300 VAC or more) for the signal wires on which a voltage of more than 30 VAC or 60
VDC is to be applied. For all other wires, use basic insulated wires (dielectric strength of 1390
VAC). Be sure to mount the terminal cover to prevent an electric shock.
Example of mechanical relay ‘a’ contact outputs
Example of mechanical relay ‘c’ contact outputs
3) Precautions for connection
Be careful with the following cautions for connections.
Item
Contents
Contact rating of
Mechanical relay outputs
(Common to ‘a’ contact
and ‘c’ contact)
Mounting of contact
protective element Z
Mount a contact protective element conforming to the buffer relay. The
relay is broken, if a signal exceeding the contact rating is applied even if
momentarily.
To prevent a malfunction being caused by a light load, the most effective
mounting position for the element is on the coil side of the buffer relay ('a'
in the connection diagrams under (2) on 5.5)
Selection of buffer relay
(1) Coil rating ........... Less than the contact rating of output terminals
(2) Contact rating ....... More than twice the load current
A coil surge absorption element built-in type relay is recommendable.
Mount an additional buffer relay if a buffer relay satisfying the load rating is
not available.
Selection of contact
protective element
Mount a contact protective element if a surge absorption element built-in
buffer relay is not available. This element is generally composed of C
(capacitor) and R (resistor).
<Reference values of C•R> C : 0.01 µF (Rating about 1 kV)
R :100 to 150
Ω
(Rating about 1 W)
Power Supply
Load
b
a
Buffer relay
This recorder
N. O
COM
: Contact protective element
(It is recommended to mount this element on the a
side)
b
a
N. O
C
COM
N. C
※
Power Supply
Load
Buffer relay
This recorder
: Contact protective element (It is recommended to
mount this element on the a side)
※
N.C terminal - Open relay contact at alarm activation
that is the reverse action to N.O terminal.
mark of alarm output terminals
Connect a load not exceeding the specified contact
capacity to the alarm output terminals. A buffer
relay power supply is applied to the alarm output
terminals after connections. Do not touch these
terminals since an electric shock will occur. Be sure
to mount the terminal cover after connections.
Warning
Take a safety measure.
An alarm output of this recorder may become
defective caused by wrong operation,
failures, and other abnormal inputs.
Take a safety measure against an output
failure before use as occasion calls.
Caution
Power supply
Resistive load
Inductive load
100 V AC
0.5 A
0.2 A
240 V AC
0.2 A
0.1 A
30 V DC
0.3 A
0.1 A
(Minimum load)
100
μ
A 100mVDC
