Binding Posts; Fuses - Siemens MJ-4A Installation And Operation Manual

2
Using the MJ-4A & MJ-4B Operator Panel and Controls
Switch Positions for Bypassing
The front panel switches must be in the following posi-
tions before bypassing the regulator.
• Auto / Manual - OFF (MJ-4A)
Auto / Manual - Remote Auto Inhibit LED=ON(MJ-4B)
• Remote Switch - Remote Disabled LED is ON
• Power Switch - OFF
Possible explosion if bypassed while
not on neutral.
Will cause death, serious injury, or
property damage.
To prevent:
Place regulator in neutral position before
bypassing and disable control panel.
See Appendix E for details.
2.6

Binding Posts

Front panel binding posts are dual banana-style
receptacles on standard 0.74 inch centers.
External Source Binding Posts
These binding posts can be used to apply 120 V external
power to the MJ-4 Control Panel when the power source
switch is in the External Source position. The binding
posts are dual banana-style receptacles.
Ensure that any voltage source attached to these binding
posts is properly polarized.
Note:
Improper external power connection will
place 120V on the ground circuit.
May result in minor or moderate injury
including equipment damage.
To prevent:
Observe proper polarity of external power
supply.
Voltage Calibration Binding Posts
These binding posts can be used with an external voltme-
ter to monitor regulator P2 or U2 voltage. Displaying "U2
Siemens Energy, Inc.
DANGER
CAUTION
Cal" or "P2 Cal" in the <DIAGNOSTICS> menu defines
the voltage (U2 or P2) you can read at these binding posts.
The binding posts are dual banana-style receptacles.
Note that the voltage measured at these binding posts is
not turns-ratio corrected. By contrast, the metered voltage
presented on the display screen (under <METER>) is cor-
rected by control-program software. (See Section 4.3.7
and Section 4.3.8 for configuring the voltage transformer
U2/P2 turns ratio).
Voltage applied at calibration terminals may
energize regulator with high voltage through
voltage transformer.
Could result in death or serious injury.
To prevent:
Do not connect any voltage source at the
voltage calibration terminals.
2.7

Fuses

Power Fuse
This 6.0 Amp fuse protects the MJ-4 Control Panel circuit
and the tap changer motor circuit.
Sensing Fuse
This 0.75 Amp slow-blow fuse protects the MJ-4 Control
Panel sensing circuit.
External Power Source Protection Fuse
This 6.0 Amp fuse protects the MJ-4 Control Panel circuit
and the tap changer motor circuit when powered through
the external source binding posts.
Hazardous voltage present on various
control leads when regulator is
energized.
Could result in death or serious injury
including equipment damage from
contact with live line conductors.
To prevent:
Bypass the regulator and de-energize
before removing accessory items from
the control box.
WARNING
WARNING
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