27
5. Cautions [Common]
1. Prevent using the timer in such places
where flammable or corrosive gas is
generated, a lot of dust exists, oil is
splashed or considerable shock and
vibration occur.
2. Since the main body cover is made of
polycarbonate resin, prevent contact with
organic solvents such as methyl alcohol,
benzine and thinner, or strong alkali
materials such as ammonia and caustic
soda.
3. External surge protection may be
required if the following values are
exceeded. Otherwise, the internal circuit
will be damaged.
4. For connecting and disconnecting
operating voltage to the timer, a circuit
should be used to prevent the flow of
leakage current. For example, a circuit
for contact protection as shown in Fig. A
will permit leakage current to flow
through R and C, causing erroneous
operation of the timer. Instead, the circuit
shown in Fig. B should be used.
5. In order to maintain the characteristics
of the timer, long continuous current flow
through the timer, causing generation of
heat internally should be avoided
because of the degradation it can cause.
For such long continuous operation, the
circuit shown below should be used.
Operation voltage
100 to 240V AC
100 to 120V AC
200 to 240V AC
48 to 125V DC
Surge voltage
4,000V
12V DC, 24V DC
24V AC
24V AC/DC
500V
No good
Leak current
(Fig. A)
C
R
T
Power
supply
Good
(Fig. B)
C
R
T
Power
supply
R: contacts of
relay
R
T
T
Time
R Relay
R
R
Surge wave form [±(1.2
×
50)µs single
polarity full wave voltage]
Notes for PM4H series
Even if the open collector is not used,
input is also possible from the non-con-
tact circuit of 6 to 30V DC. In this case,
the signal input is turned on when the
signal is turned from H to L.
The residual voltage must be 0.6V or
less when Q is on. On the AC type, an
insulated transformer is required as the
power supply for the photoelectric sen-
sor, etc. (power supply for the input
devices).
Note: Keep the minimum input signal time of
each signal to 0.05s or more.
4. Power off time
Keep 0.1s (-A, -S, -M type), 0.5s (-SD/
SDM type), 0.3s (-W type) or more for
the power off time after time cycle is
completed.
Internal circuit
with photoelectric
sensor, etc.
(The signal input
is turned on at
L level.)
[Example of
signal input]
1mA
Q
3) Voltage input
0
0
1.2
50
30
50
Time
Crest value
100
90
(
µ
s)
Crest value (%)
Apply the open-collector connection. The
characteristics of the transistor used
must be V
CEO
=10V or more, I
C
=10mA or
more, and I
CBO
=6µA or less. Additionally,
the input impedance must be 1k
Ω
or
less, and the residual voltage must be
0.6V or less.
Reset input
Signal input
Stop input
2) Connections of non-contact input
(open-collector)
02/2003
