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コントロールユニット Clark Cooper EH40-04のPDF 設置および操作マニュアルをオンラインで閲覧またはダウンロードできます。Clark Cooper EH40-04 7 ページ。
ページを印刷するIn some systems, it may be useful to install a flyback diode to protect the circuit. The flyback
diode prevents sparking between the contacts of the switch that controls power to the DC coil.
When the circuit is closed, current flows through the coil and a magnetic field builds inside of
the coil winding. Current does not flow through the diode as long as the breakdown voltage of
the diode is higher than the voltage across the coil. When the switch is opened, the magnetic
field inside of the coil starts to dissipate and in doing so, generates current in the coil and can
create a very large negative voltage spike. Because of the large potential, sparks can jump
between the contacts of the switch if there is no flyback diode. With the flyback diode, there is
still a closed circuit for the current to flow through even though the switch is open. The current
will flow through the loop between the diode and the coil until all of the energy is lost and will
not spark across the switch.
The UF4001-UF4007 series of diodes may be used as flyback diodes for circuit protection from
DC coils. These diodes will handle the low current that is created by the magnetic field after the
coil is turned off. Because they are fast acting, the decay time of the flyback current will be
relatively shorter compared to other diodes. The table below shows what specific diode should
be used for certain coil voltages.
The table of diodes is a suggestion ONLY. The entire circuit should be designed and analyzed by
a licensed Professional Electrician or an Electrical Engineer. The Clark Cooper Division of
Magnatrol Valve Corporation is not responsible for electrical system damage due to faulty wiring
or inadequate protections.
DIN Connector Option Pin-out:
Coil Voltage Flyback Diode
12V DC
UF4001
24V DC
UF4001
120V DC
UF4004
Figure 3. DIN Type A male pinout.
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Roebling, nj 08554
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