KW1M-H Eco-POWER METER
9
3.4 For input connection
・
Contact input
Use highly reliable metal plated contacts. Since the contact’s
bounce time leads directly to error in the count value, use
contacts with as short a bounce time as possible. In general,
select 30Hz for max. counting speed.
・
Non-contact input (Transistor input)
Connect with an open collector. Use the transistor with the
following specifications. V
CEO
=20V min. I
C
=20mA min. I
CBO
=6
μ
A max
Use transistors with a residual voltage of less than 1.5V when the transistor is ON.
＊
Short-circuit impedance should be less than 1k
Ω
.
(When the impedance is 0
Ω
, drain current is approx. 7mA.)
Open-circuit impedance should be more than 100k
Ω
.
・
Input wiring
Please wire up to 10m by using a shielded wire or a metallic electric wire tube individually.
If it is long, it may not work correctly due to floating capacitance of wire.
(Note)
Operating power supply input part and measured voltage input are not insulated to pulse input parts.
So the input equipment must have the power supply transformer in which the secondary side is not
grounded with the primary and secondary sides insulated, in order to prevent interference of the
power supply circuit when connecting the external input circuit. Be sure not to use an
auto-transformer.
⑬
⑭
P.IN +
P.IN
－
Eco-POWER
METER
(
＋
)
(
－
)
Insulated
transformer
Input equipment
(sensor etc.)
Operating power supply
Measured voltage input
(Fig. A)
Good example
Eco-POWER
METER
(
＋
)
(
－
)
Eco-POWER
METER
Auto transformer
(Fig.B) No Good example
Do not ground the secondary side.
Do not use an auto-transformer.
Operating power supply
Measured voltage input
Operating power supply
Measured voltage input
Insulated
transformer
Input equipment
(sensor etc.)
Input equipment
(sensor etc.)
(
＋
)
(
－
)
