Minster SCRB-68, Руководство пользователя

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1. Place the POWER, OFF-ON Selector Switch in the
OFF position and lock the electrical disconnect
switch in the OFF position. Then open the electrical
control panel to obtain access to the SCR-22/28
unit.
2. Disconnect the wires from the terminals on the
SCR-22/28 unit. The wires will be re-connected to
the new unit, therefore, make certain the wires are
labeled before disconnecting them. Also the correct
wire number from the wire being taken off of the
SCR-22/28 should be written into the blanks above
the terminals on Figure 9.
3. Loosen the four (4) mounting screws that secure
the SCR-22/28 unit to the panel just enough to per-
mit removal of the unit. Then remove the unit from
the control panel.
4. Install the SCRB-68 unit in the control panel and
tighten the four (4) associated mounting screws
securely.
5. Connect the wires (previously removed in Step 2) to
the terminals on the SCRB-68 unit. Refer to Figure
8 for wiring details.
NOTE: A jumper must be installed between termi-
nals 5 and 7 on the SCRB-68. Failure to
install this jumper will result in an inoperable
SCRB-68.
6. The fuse holder (furnished) should be installed as
close to the 100 Volt transformer as possible. Begin
by drilling and tapping two (2) #10 - 24 holes in the
control panel to anchor the fuse holder. Then mount
and secure the fuse holder to the panel.
CAUTION
WHEN DRILLING AND TAPPING HOLES FOR THE
FUSE HOLDER MAKE SURE THAT NO METAL
SHAVINGS FALL ON ANY CIRCUIT BOARDS OR
ANY OTHER ELECTRIC DEVICES.
7. Remove the wire from terminal “Y1” of the trans-
former and re-label it “1Y1”. (NOTE: Re-label both
ends of the wire.) Then attach the wire to the bottom
side of the fuse. (See Figure 8.)
8. Run a #16 gauge MTW grade wire (or equivalent)
from the top of the fuse to terminal “Y1” of the 100
Volt transformer. Label this wire “Y1”.
9. After completing Steps 1 through 8, close up the
electrical control panel. Then refer to the Adjust-
ment section of this manual.
While the SCR-22/28 control uses a 500 ohm speed
control potentiometer, and the SCRB-68 uses a 1000
ohm potentiometer, use of the 500 ohm potentiometer
will not damage the SCRB-68. This control should work
normally except in some instances the 15 Volt DC ref-
erence supply may lose its controlled regulation, result-
ing in slight, speed changes if the plant voltage
changes.
If the SCRB-68 control installation is to be permanent,
it is suggested that the 1000 ohm speed control poten-
tiometer be installed.
INSTALLATION NOTE:
A troubleshooting guide is included as a part of this
manual to aid technicians in restoring normal control
functions, should the need occur. It is recommended
that this unit not be dismantled for repair. Minster does
not stock or supply internal components for this unit.
Return unit to Minster for repair.
As mentioned previously, the unit contains potentiome-
ters which must be adjusted to suit operating conditions
of the control.
During the process of troubleshooting a control mal-
function, do not overlook the fact that a problem could
exist within the eddy current coupling or its associated
drive motor. Some of the suggested checks in the trou-
bleshooting guide are included to help determine
whether a problem exists in that area.
If it should become necessary to disassemble the
motor or coupling, follow step-by-step procedure out-
lined in the motor manufacturer’s instructional manual.
If trouble should develop within the tachometer gener-
ator, disassembly of the coupling housing will usually
be required since the generator is normally attached to,
or located just inside, the coupling end bell. Use cau-
tion when disassembling this part. The tachometer
generator should never be subjected to sharp blows or
heat.
Air-cooled eddy current coupling rotating equipment
requires ample quantities of clean, cooling air. Exhaust
air must be permitted to flow away from the drive and
not be returned. For most efficient use of the equip-
ment, make certain that air inlets and exhaust outlets
are not obstructed in any way that would tend to reduce
air flow or cause recirculation of the heated exhaust air.
Establish periodic cleaning and lubrication schedules
for the drive. Use dry compressed air of moderate pres-
sure to dislodge and remove foreign matter from air
intake screens or louvers. If dirt or foreign matter accu-
mulates inside, it will then become necessary to disas-
semble the drive in accordance with manufacturer’s
instructions and clean with an approved cleaning solu-
tion. At the same time, inspect condition of windings
and insulation. After cleaning, reassemble per instruc-
tions.
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