889-3819-00
MMU2-1600GE series Operations Manual Rev Apr 2020 Page
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Minimum Yellow Change Disable Jumpers
: When Minimum Yellow Change Disable is jumpered for a
channel the Red + Yellow fault timing threshold for the single indication timer is changed from 1000
milliseconds to 400 milliseconds.
Flashing Greens (also known as Canadian Fast Flash)
: When Flashing Greens are enabled the no indication
timer thresholds for the Green + Red and Green + Yellow fault conditions are changed from 300 milliseconds
to 100 milliseconds.
Flashing Yellow Arrow Left Turns
: The Dual indication setting for a FYA channel is associated to the channel
that has the green indication (Parent channel). The MMU will interpret the 4 indications for FYA. It will
perform the additional tests of Red + FYA, FYA, and Green + FYA.
If GREEN SOLO is selected and IGNORE UNUSED CHAN is YES, the unused Red and Yellow signals of
the FYA parent channel is ignored for Dual Indication.
If FYA SOLO is selected, the channel must have both RED ENABLE and FIELD CHECK/DUAL
INDICATION OFF, no MYCD jumper, and is not selected as a pedestrian channel then the unused indication
(Green or Yellow) of the FYA channel is ignored for Dual Indication.
LED Thresholds
: When LED Thresholds is enabled the monitor senses Greens, Yellows, Reds, and Walks as
ON when their voltage is above 25V
RMS
and OFF when below 15V
RMS
for the dual indication test.
2.5.4
GY-DUAL INDICATION MONITORING
Configuration:
Green-Yellow Monitoring Enabled is used to enable monitoring for this fault. When enabled all
channels will have a minimum of Green + Yellow dual indication monitoring. All channels with a setting of “Y”
for Dual Indication / Field Check will be monitored for all dual indication fault combinations (See Section 2.5.3
for
fault combinations). The testing default for this feature is disabled.
Test Preformed:
When a channel has a Green and a Yellow display active a dual indication timer is started. If one
of the indications turns off the dual indication timer is stopped (it is not cleared) and a single indication timer is
started. If both of the indications turn off the dual indication timer is stopped (it is not cleared) and a no indication
timer is started. If the dual indication condition returns the single indication and no indication timers are stopped
(not cleared) and the dual indication timer continues timing from its prior value. If the dual indication timer
reaches 600 milliseconds or more the monitor will latch a dual indication fault. If the single indication timer
reaches 1000 milliseconds the dual indication timer, the single indication timer, and the no indication timer are
reset to zero and the dual indication is ignored. If the no indication timer reaches 300 milliseconds the dual
indication timer, the single indication timer, and the no indication timer are reset to zero and the dual indication is
ignored. The normal voltage thresholds for this test are: Reds – ON when above 70V
RMS
and OFF when below
50V
RMS
, Greens / Yellows / Walks – ON when above 25V
RMS
and OFF when below 15V
RMS
.
Fault Action:
The monitor transfers the Output relay contacts to the fault condition (continuity between the
Normally Open and Common contacts), illuminates the
DUAL IND
indicator on the front panel, and sets the Spare
Bit #2 bit (bit 68) of the Type 129 Frame to 1. The Signal Sequence log and the Prior Faults log will record this
fault.
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:
Red Enable
: All Green + Yellow dual indication testing will be disabled when this input is below 70V
RMS
.
Load Switch Flash bit (bit 112) of the Type 0 Frame
: All Green + Yellow dual indication testing will be
disabled when this bit is set to one.
Feature Interactions:
Flashing Greens (also known as Canadian Fast Flash)
: When Flashing Greens are enabled the no indication
timer threshold for the Green +Yellow fault condition is changed from 300 milliseconds to 100 milliseconds.
LED Thresholds
: When LED Thresholds is enabled the monitor senses Greens, Yellows, Reds, and Walks as
ON when their voltage is above 25V
RMS
and OFF when below 15V
RMS
for the dual indication test.
2.5.5
SHORT YELLOW MONITORING
Configuration:
Minimum Yellow Change Disable (MYCD) jumpers on the program card disable short Yellow
monitoring for a channel. Typically pedestrian only channels will have MYCD jumpers installed. The testing
defaults for this feature are determined by the jumpers installed on the program card. Typically no jumpers are
installed during automated testing.
Test Preformed:
When a channel has a Green that turns off, a Yellow must follow it and it must stay on for at
least 2.7 seconds. When each Green turns off a 2.7 second timer is started. A Yellow must start within 1 second of
the Green turning off. If the Red turns on before the Yellow, a short Yellow fault will be generated to show that
