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MMU2-1600GE series Operations Manual Rev Apr 2020 Page
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Fault Action:
The monitor transfers the Output relay contacts to the fault condition (continuity between the
Normally Open and Common contacts), illuminates the
CVM / WD
indicator on the front panel, and sets the
Controller Voltage Monitor bit (bit 57) of the Type 129 Frame to 1. The Signal Sequence log will record this fault.
The Prior Faults log will record this fault if Log CVM Events is enabled.
Resetting the Fault:
Restoration of proper voltage to the CVM input will reset this fault. Once tripped to the fault
state, the minimum flash time must time before normal operation can be restored. The Reset log will record the
resetting of this fault.
If the CVM Latch jumper is installed on the Program Card, the monitor remains in this fault condition until the unit
is reset by the activation of the front panel reset pushbutton or the activation of the reset input. Power loss or
power interruption will not reset this fault.
Modifying Inputs:
None
Feature Interactions:
Modified CVM Latch
: When this feature is enabled and the CVM Latch jumper is installed the monitor will
not latch a CVM fault until the CVM input has been valid (Low) for more than 175 milliseconds. This feature
is useful in cabinets where the CVM input may not always be valid within the programmed Minimum Flash
time and where latched CVM failures is desired.
Log CVM Events
: When this feature is enabled the Prior Faults log will record this fault. Disabling this
feature is useful when the intersection uses the CVM input to provide time of day flash. This will keep the
Prior Faults log from filling up with normal flash operations.
2.5.12
LOCAL FLASH
Configuration:
None
Test Preformed:
A voltage of less than 8V
DC
(low) is recognized as a request for Local Flash. A voltage greater
than 16V
DC
(or floating) is recognized as normal operation. When the Local Flash input is detected as low for
more than 175 milliseconds, the monitor generates a fault. A Local Flash request during the programmed
Minimum Flash time shall not cause a fault.
Fault Action:
The monitor transfers the Output relay contacts to the fault condition (continuity between the
Normally Open and Common contacts), illuminates the
LOC FLASH
indicator on the front panel, and sets the
Local Flash bit (bit 79) of the Type 129 Frame to 1. The Signal Sequence log will record this fault. The Prior
Faults log will record this fault if Log Local Flash Events is enabled.
Resetting the Fault:
Restoration of a voltage greater than 16V
DC
(or floating) to the Local Flash input will reset
this fault. Once tripped to the fault state, the minimum flash time must time before normal operation can be
restored. The Reset log will record the resetting of this fault.
Modifying Inputs:
None
Feature Interactions:
Disable Local Flash
: When this feature is enabled and the Local Flash input will be ignored.
Log Local Flash Events
: When this feature is enabled the Prior Faults log will record this fault. Disabling this
feature is useful when the intersection uses the Local Flash input to provide time of day flash. This will keep
the Prior Faults log from filling up with normal flash operations.
2.5.13
EXTERNAL WATCHDOG MONITORING
Configuration:
The setting of External Watchdog Enable determines if this feature is active. The testing default
for this feature is disabled.
Test Preformed:
The External Watchdog input is connected to Pin S on Connector B (Spare 2). A voltage of less
than 8V
DC
is recognized as a low and a voltage greater than 16V
DC
is recognized as a high. The input must change
states at least once every 1500 milliseconds or the monitor generates a fault. A External Watchdog fault during the
programmed Minimum Flash time or during a monitor Power Failure shall not cause a fault.
Fault Action:
The monitor transfers the Output relay contacts to the fault condition (continuity between the
Normally Open and Common contacts), flashes the
CVM / WD
indicator on the front panel, and sets the Spare Bit
#4 (bit 70) of the Type 129 Frame to 1. The Signal Sequence log will record this fault. The Prior Faults log will
record this fault if Log Local Flash Events is enabled.
Resetting the Fault:
The monitor remains in this fault condition until the unit is reset by the activation of the front
panel reset pushbutton or the activation of the reset input. Power loss or power interruption will not reset this fault.
The Reset log will record the resetting of this fault.
Modifying Inputs:
None
