BECKWITH ELECTRIC M-6280A, Инструкция

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M-6280A Instruction Book
4–84
Capacitor Bank Switch Type Selection
Pole top capacitor bank switches appear to fall
into one of two main categories for their actuating
mechanisms; solenoid driven switches and
motor driven switches. There also appear to be
combinations of these that Open with one method
and Close with another. Please consult the factory
if it is not obvious how to program the M-6280A for
a given cap bank switch type.
Solenoid Driven Switches use Open and/or
Close motor coils to pull in a moveable actuator
that is mechanically connected to the interrupting
medium switch contacts. These contacts connect
and disconnect each phase’s capacitor(s) from the
feeder. The actual interrupting medium can include
vacuum, gas, oil, air, or solid dielectrics.
These solenoid motor coils typically draw in excess
of 10 Amperes at 120 VAC for each phase, for a
short time duration while the actuator is in transit.
Typical values are several cycles, (20 to 40 ms).
Some motor coils disconnect after the actuator
operates, and some do not. Those that do not
disconnect, continue to draw a substantial current,
until the control output shuts off.
To prevent unnecessary current draw and
subsequent heating, the control has an output timer
range for use with solenoid switches that is user
settable between 50 and 150 ms.
Motor Driven Switches use a Geneva Drive-type
mechanism with a small bi-directional motor that
typically stores energy in a mechanical spring.
That spring actuates the high voltage, high current
switch contacts. These motors usually run from
2 to 5 seconds to load the spring for a switching
operation that lasts a few milliseconds. The motor
runs in one direction for an Open operation and in
the opposite direction for a Close operation. The
switch has auxiliary contacts that open the motor
winding circuit just actuated, eliminating a stalled
rotor condition since the motor cannot continue in
that direction after switching once without switching
in the opposite direction.
To match these characteristics, the control includes
an output timer range for use with motor driven
switches that is user settable between 5 and 30
seconds.
Close/Open Pulse Duration
Close/Open Pulse Duration is the period of time that
the Close or Open contact stays energized.
Selecting Capacitor Bank Switch Type and
Close/Open Pulse Duration From The HMI
1. Press the Down Arrow (CNFG Hot Button)
pushbutton to awaken the unit. The menu
will advance to "CONFIGURATION".
CONFIGURATION

SETP COMM

2. Press the Down Arrow pushbutton once.
The unit will display the following:
Cap Settings
 
3. Press the Right or Left Arrow pushbuttons
as necessary until the "Common
Settings" screen is displayed.
Common Settings
 
4. Press the Down Arrow pushbutton as
necessary to navigate to the "Switch
Control Type" menu item.
Switch Control Type
Solenoid Driven
5. Press the "ENT" pushbutton. If Level
Access is not active or has been
previously input, then the following will
be displayed. Go to Step 8.
Switch Control Type
Solenoid Driven
C
6. If Level Access is active, then the Level
Access prompt will be displayed.
ENTER LEVEL ACCESS
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