Panasonic KW8M, Руководство пользователя

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KW8M Eco-POWER METER
9
Without Ammeter
3.3 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
=6μA max
Use transistors with a residual voltage of less than 1.5V when the transistor is ON.
*`Short-
circuit impedance should be less than 1kΩ.
(When the impedance is 0Ω, drain current is approx. 7mA.)
Open-
circuit impedance should be more than 100kΩ.
・
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.
Secondary current
Breaker
Power supply
CT with 2nd current 5A
K
L
Load
Dedicated CT for 5A
L K
Eco-POWER
METER
Shorted or resistor less than 0.1
Ω
Eco-POWER
METER
(
＋
)
(
－
)
Insulated
transformer
Input equipment
(sensor etc.)
Operating power supply
Measured voltage input
(Fig. A)
Good example