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MMU2-1600GE series Operations Manual Rev Apr 2020 Page
13
of 51
2.5.7
FIELD CHECK MONITORING
Configuration:
All channels with a setting of “Y” for Dual Indication / Field Check will be monitored for a field
check fault. The testing defaults for this feature are all channels enabled for field check testing.
Test Preformed:
This monitoring function combines information about active field inputs with information
received through the Port 1 communications between the Controller Unit and the monitor in a TS 2 Cabinet
Assembly. The monitor will receive a Type 0 Frame from the Controller Unit (Type 1 or Type 2 CU) that contains
an image of the controller output commands to the load switches. When the field signal input states detected as
active or inactive by the monitor do not correspond with the information received from the Controller Unit in the
Type 0 Frame for 10 consecutive 100 millisecond periods a fault will be generated. The normal voltage thresholds
for this test are: Reds – ON when above 70V
RMS
and OFF when below 50V
RMS
, Greens, Walks, and Yellows – 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
FIELD CHK
indicator on the front panel, and sets the
Spare Bit #1 bit (bit 67) 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 field check testing will be disabled when this input is below 70V
RMS
.
Port 1 Disable
: All field check testing will be disabled when this input is below 8V
DC
.
Feature Interactions:
Dual Indication
: Enabling field check monitoring will also enable dual indication monitoring.
Per Channel Red Enables
: When Co-Channel / Per Channel Red Enables are enabled, only channels that have
been programmed with a Per Channel Red Enable setting of “Y” will be included in the channels checked for
a field check fault.
Flashing Don’t Walk Monitoring
: When channels are programmed as Channels with Pedestrian Displays, the
yellow of the active channels will not be checked for a field check fault. This does not require that the
Flashing Don’t Walk Monitoring Enable be set to ON.
2.5.8
PORT 1 FAIL MONITORING
Configuration:
If operating in the Type 16 mode, Port 1 timeouts will always be checked for unless Port 1 Disable
(SDLC Connector - Pin 10) is low. The testing default for this feature is determined by the Port 1 Disable pin.
Test Preformed:
If the monitor has not received a Type 0 Frame from the Controller Unit through the Port 1
SDLC communications bus for 300 milliseconds (three consecutive frame periods) a Port 1 fault will be generated.
A Port 1 Timeout failure 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), illuminates the
PORT 1 FAIL
indicator on the front panel, and sets the
Port 1 Timeout bit (bit 75) of the Type 129 Frame to 1. The Signal Sequence log and the Prior Faults log will
record this fault.
Resetting the Fault:
When receipt of 10 consecutive valid Type 0 Frames occurs, the monitor will transfer the
Output relay contacts to the No Fault state unless three Port 1 timeouts have occurred in a calendar day. The
monitor will not exit this third timeout state without user interaction (activation of the front panel reset pushbutton
or activation of the reset input) or AC power being removed and reapplied. A user interaction will reset Port 1
Timeout counts to zero. AC power interruptions will not reset this count. When the monitor’s clock passes
through midnight, the count will be reset to zero. The Reset log will record the resetting of this fault.
Modifying Inputs:
Port 1 Disable
: Port 1 failures will be ignored when this input is below 8V
DC
.
Type Select
: Port 1 failures will be ignored when this input is in the Type 12 mode (Unterminated or above
16V
DC
).
Feature Interactions:
None
