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3) Precautions
on
wiring
The following are precautions on wiring.
Item
Description
Mechanical relay output
specification contact
capacity
(Common to ‘a’ contact
and ‘c’ contact)
Power supply
Resistance load
Inductive load
100VAC 2A
1A
240VAC 2A
1A
30VDC 2A
1A
Contact protective element
Z installation
Install the contact protective element which fits the buffer relay.
It is effective to install the element to the coil side of the buffer relay (see the figure
of mechanical relay ‘a’ contact output example) and prevents wrong operation with
light load.
Selection of buffer relay
Coil rating: Contact capacity or less of output terminals
Contact rating: Double of load current or more
In addition, the coil surge absorption element built-in type relay is recommended. If
there is no buffer relay which meets the load rating, implement another stage of buffer
relay.
Selection of contact
protective element
If there is no surge absorption element built-in buffer relay, install this element.
The element of C/R (cap resistor) is general.
<C/R standard> C: 0.01
μ
F (Rating about1kv)
R: 100 to 150
Ω
(Rating about 1W)
(Minimum load)
100
μ
A100mVDC
