H3CR-A Datasheet, PDF (21/22 Pages) Omron Electronics LLC – Solid-state Multi-functional Timer

Precautions (H3CR-A)
Note: The undermentioned is common for all H3CR-A models.
I Power Supplies
For the power supply of an input device of the H3CR-A@/-A@S/-AP,
use an isolating transformer with the primary and secondary wind-
ings mutually isolated and the secondary winding not grounded.
Example: H3CR-A
G, S, R
5, 6, 7
2
H3CR-A
10
Input
terminal
2
Power supply
Input device
Isolation transformer is required.
The H3CR-A@/-A@S/AP’s power supply terminal 2 is a common ter-
minal for input signals to the Timer. Do not disconnect the wires on
terminal 2, otherwise the internal circuitry of the Timer will be dam-
aged.
5, 6, 7
G, S, R
Input terminal
10
H3CR-A
2
Make sure that the voltage is applied within the specified range, oth-
erwise the internal elements of the Timer may be damaged.
I Input/Output
Relationship between Input and Power
Supply Circuits (except for H3CR-A8E)
The H3CR-A (except for H3CR-A8E) uses transformerless power
supply. When connecting a relay or transistor as an external signal
input device, pay attention to the following points to prevent short-cir-
cuiting due to a sneak current to the transformerless power supply. If
a relay or transistor is connected to two or more Timers, the input ter-
minals of those Timers must be wired properly so that they will not
differ in phase, otherwise the terminals will be short-circuited to one
another.
Incorrect
Contact or transistor for
external input signal
H3CR-A
Input
terminal
Short-circuit current
Power supply
Correct
Input
terminal
Input
terminal
Power supply
Input
terminal
It is impossible to provide two independent power switches as shown
below regardless of whether or not the Timers are different in phase.
Input
terminal
Power supply
Input
terminal
Solid-state Multi-functional Timer H3CR-A B-129