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    BAS Controls Fault Codes

    429 codes for building automation. Johnson Controls Metasys, Tridium Niagara, Distech, Schneider, Siemens Desigo, ALC WebCTRL, plus BACnet and Modbus.

    BAS Controls Fault Codes

    Building automation alarms, BACnet faults, and Modbus exceptions for Johnson Controls Metasys, Honeywell / Tridium Niagara, Distech, Schneider EcoStruxure, Siemens Desigo, Automated Logic, KMC, and more.

    Coverage
    429codes
    12 controllers across 12 brands
    Filter by brand / controller
    Browsing all 429 codes · page 1 of 9
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-001 — NAE CPU Usage High
    Warning

    NAE CPU utilization exceeds factory-set alarm threshold. Diagnostic attribute on Device object generates an event.

    Likely Causes
    • Too many field devices on trunk
    • High scan-rate polling
    • Excessive COV subscriptions
    • Heavy reporting workload
    First Checks
    • Check NAE Diagnostic tab for CPU Usage value
    • Reduce polling frequency on large device lists
    • Review COV increment settings
    • Check number of active event subscriptions
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0 – Alarms and events, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-002 — NAE CPU Temperature High
    Warning

    CPU die temperature on NAE exceeds factory alarm limit. Built-in diagnostic.

    Likely Causes
    • Inadequate ventilation in control panel
    • Ambient temperature above spec
    • Fan failure in enclosure
    • Controller mounted in direct sunlight
    First Checks
    • Verify panel ambient temperature
    • Check enclosure ventilation
    • Inspect for heat sources near controller
    • Consider relocating controller
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0 – Device diagnostic features table, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-003 — NAE Memory Usage High
    Warning

    NAE RAM usage exceeds alarm threshold.

    Likely Causes
    • Too many objects in engine database
    • Excessive trending configuration
    • Large audit log backlog
    • Software memory leak
    First Checks
    • Review total object count in SCT
    • Check trend log configuration
    • Verify ADS/ADX is online and forwarding events
    • Consider engine firmware update
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-004 — NAE Flash Usage High
    Warning

    Non-volatile flash storage on NAE approaching capacity.

    Likely Causes
    • Large number of stored events not forwarded
    • Accumulated firmware update files
    • Log data overflow
    • ADS/ADX offline preventing event forwarding
    First Checks
    • Verify ADS/ADX connectivity
    • Check event repository settings
    • Review flash usage on Diagnostic tab
    • Delete old firmware update files if applicable
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-005 — NAE Audit Rate High
    Information

    Rate of audit events (operator actions) exceeds alarm threshold.

    Likely Causes
    • Automated scripts performing frequent commands
    • Mass override operations
    • Integration polling with write-backs
    • Security testing or scanning
    First Checks
    • Review operator activity logs
    • Disable automation scripts if unexpected
    • Check third-party integrations for excessive writes
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-006 — NAE Event Rate High
    Warning

    Rate of alarm/event generation exceeds alarm threshold.

    Likely Causes
    • Rapidly oscillating analog value around alarm limit
    • Mass communication loss on trunk
    • Misconfigured alarm deadband (too narrow)
    • Sensor noise or input instability
    First Checks
    • Identify highest-frequency alarm sources in Event Viewer
    • Widen deadband on oscillating points
    • Check SA bus or FC trunk for communication issues
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-007 — NAE Events Lost
    Warning

    NAE event repository became full and events were discarded before forwarding to ADS/ADX.

    Likely Causes
    • ADS/ADX server offline for extended period
    • Network path to ADS/ADX unavailable
    • Repository size too small for site alarm volume
    • Alarms not being acknowledged/cleared
    First Checks
    • Verify ADS/ADX server online status
    • Check Ethernet connectivity to site director
    • Review repository settings in engine properties
    • Acknowledge and clear backlog of alarms
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-008 — NAE Samples Lost
    Warning

    Trend log samples were lost due to buffer overflow.

    Likely Causes
    • ADS/ADX offline preventing trend upload
    • Very short sampling interval with many trend objects
    • Network congestion
    • Trend buffer undersized for interval
    First Checks
    • Verify ADS/ADX connectivity
    • Review trend sample intervals
    • Check 'Transfer Buffer Full' diagnostic
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-009 — NAE Sample Rate High
    Warning

    Trend sampling rate exceeds the engine's processing capacity.

    Likely Causes
    • Too many trend objects with very short intervals
    • Combined sample rate too high for CPU
    • Excessive COV-triggered trends
    First Checks
    • Review all trend object intervals
    • Reduce sample rate on non-critical trends
    • Stagger trend intervals to distribute load
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-010 — NAE Transfer Buffer Full
    Warning

    The buffer used to transfer trend data to ADS/ADX is full.

    Likely Causes
    • ADS/ADX temporarily offline
    • Network outage between NAE and server
    • High trend sample volume
    First Checks
    • Check ADS/ADX server status
    • Verify LAN path to server
    • Reduce trend frequency during outage
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-011 — NAE BACnet Broadcast Receive Rate High
    Warning

    BACnet I-Am or Who-Is broadcast traffic on the IP network exceeds threshold.

    Likely Causes
    • Misconfigured BBMD creating broadcast storm
    • Many devices restarting simultaneously
    • Third-party device constantly broadcasting
    • Network misconfiguration causing loop
    First Checks
    • Capture BACnet/IP traffic with Wireshark
    • Identify source of broadcasts
    • Check BBMD configuration
    • Verify BACnet network numbers are unique
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-012 — NAE COV Receive Rate High
    Warning

    Rate of Change-of-Value (COV) notifications received by NAE exceeds threshold.

    Likely Causes
    • COV increment set too low causing frequent notifications
    • Many active COV subscriptions
    • Field device sending COV for every scan cycle
    First Checks
    • Review COV increment values on high-traffic points
    • Check number of active COV subscriptions
    • Increase COV increment on non-critical AI objects
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-013 — SNE/SNC Events Lost Counter Incrementing
    Warning

    SNE/SNC alarm event buffer for offline Metasys Server exceeded 1,000 events and is discarding new events.

    Likely Causes
    • Metasys Server offline for extended period
    • Network outage
    • Server overloaded or crashed
    • License issue preventing server operation
    First Checks
    • Verify Metasys Server status
    • Check network path between SNE and server
    • Review server event logs
    • Restart server if frozen
    Source: Metasys SNE Commissioning Guide LIT-12013352 v15.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-014 — Analog Alarm – High Alarm
    Warning

    Analog point Present Value has exceeded the configured High Alarm Limit for at least the Time Delay period.

    Likely Causes
    • Process variable genuinely high
    • Sensor out of calibration reading high
    • Input wiring fault causing erroneous high signal
    • Setpoint reference misconfigured
    First Checks
    • Verify actual process value independently
    • Check sensor calibration and offset
    • Review High Alarm Limit configuration
    • Inspect input wiring for shorts or grounds
    Source: Metasys SMP Help LIT-1201793 v11.0 – Alarm Extensions, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-015 — Analog Alarm – Low Alarm
    Warning

    Analog point Present Value has dropped below the configured Low Alarm Limit.

    Likely Causes
    • Process variable genuinely low
    • Sensor failure or open circuit reading low
    • Power loss to transmitter
    • Low Alarm Limit set too close to normal range
    First Checks
    • Verify actual process value
    • Check sensor power and signal
    • Review Low Alarm Limit value
    • Test with known input source
    Source: Metasys SMP Help LIT-1201793 v11.0 – Alarm Extensions, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-016 — Analog Alarm – High Warning
    Information

    Analog point Present Value exceeded the High Warning threshold (offset above High Warning Reference), but not yet the High Alarm Limit.

    Likely Causes
    • Process approaching high alarm condition
    • Gradual drift in controlled variable
    • Seasonal load change
    First Checks
    • Review trend data for the point
    • Check setpoint and control loop performance
    • Verify High Warning Offset value
    Source: Metasys UI Help LIT-12011953 v8.0 – Analog alarm attributes, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-017 — Analog Alarm – Low Warning
    Information

    Analog point Present Value dropped below the Low Warning threshold.

    Likely Causes
    • Process approaching low alarm condition
    • Gradual drift in controlled variable
    • Seasonal load change
    First Checks
    • Review trend data
    • Check control loop
    • Verify Low Warning Offset value
    Source: Metasys UI Help LIT-12011953 v8.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-018 — Binary/Multistate Alarm – Trouble
    Warning

    Multistate or binary point entered a configured Fault Value (Fault Values list) — a state that indicates a fault condition distinct from normal off-normal.

    Likely Causes
    • Field device reporting a fault state via multistate object
    • Equipment fault relay closed
    • VFD reporting fault via network status point
    First Checks
    • Identify what state value the object entered
    • Investigate the field device's own fault indicators
    • Check Fault Values configuration in alarm extension
    Source: Metasys SMP Help LIT-1201793 v14.0 – BACnet Alarm Tab, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-019 — Alarm State – Offline
    Warning

    An object or field device has gone offline/unreachable as detected by the alarm monitoring system.

    Likely Causes
    • Field device powered down
    • SA bus or FC trunk communication failure
    • Device address conflict on network
    • Cable fault or termination issue
    First Checks
    • Check LED indicators on field device
    • Verify power to device
    • Inspect bus wiring and terminations
    • Check for address conflicts in SCT
    Source: Metasys UI Help LIT-12011953 v8.0 – Alarm Manager alarm types, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-020 — Alarm State – Unreliable
    Warning

    A BACnet object's Reliability property is not NO_FAULT_DETECTED, indicating a sensor or communication issue. The Fault flag in Status_Flags is set TRUE.

    Likely Causes
    • Sensor disconnected (NoSensor)
    • Signal over range (OverRange)
    • Signal under range (UnderRange)
    • Open loop or short circuit on input
    • Communication failure with remote object
    First Checks
    • Read the Reliability attribute of the object
    • Check sensor wiring
    • Verify signal within expected range
    • Test sensor with multimeter
    Source: Metasys SMP Help LIT-1201793 v14.0 – BACnet Alarm Tab, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-021 — Alarm State – Command Failure (OnOff Action Failure)
    Warning

    A commanded output state did not match the feedback status within the Reference Delay Time — indicating a failed actuator or contactor.

    Likely Causes
    • Actuator or relay failed
    • Fan or pump motor tripped
    • Wiring fault between controller output and load
    • Feedback point wired incorrectly
    First Checks
    • Verify commanded state vs. actual status at device
    • Check motor starter/contactor
    • Test feedback wiring continuity
    • Review Command Reference and Reference Delay in alarm extension
    Source: Metasys YouTube LIT-12011953 – Programming a Command Status Alarm Extension; Metasys SMP Help v14.0
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-022 — Alarm State – Shutdown
    Shutdown

    Object or equipment is in a Shutdown alarm state — a critical alarm requiring intervention.

    Likely Causes
    • Life safety condition triggered
    • Equipment protective shutdown
    • Manual shutdown command
    • Loss of critical input
    First Checks
    • Identify alarm source object
    • Check equipment for fault indicators
    • Review alarm history for sequence of events
    • Restore safe conditions before reset
    Source: Metasys UI Help LIT-12011953 v8.0 – Alarm Manager alarm type list, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-023 — N2 Bus Communication Loss
    Warning

    NAE55 lost communication with one or more N2 field devices on the FC Bus (N2 Trunk). FCA or FCB LED shows steady green (transmitting only, no reply).

    Likely Causes
    • Field device powered down
    • N2 bus wiring fault
    • Incorrect termination resistor placement
    • Bus address conflict
    • Failed N2 device
    First Checks
    • Check FCA/FCB LED state on NAE55
    • Verify field device power
    • Inspect N2 wiring at both ends
    • Confirm 120-ohm termination at bus endpoints
    • Check for duplicate N2 addresses
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0 – NAE LED status indicators table, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-024 — SA Bus Communication Loss
    Warning

    NCE25 lost communication on the SA Bus (Sensor/Actuator bus). LED shows no blinking.

    Likely Causes
    • SA bus device offline
    • Wiring break on SA bus
    • End-of-line resistor missing
    • SA bus device address conflict
    First Checks
    • Check SA Bus LED on NCE25 (5 Hz blink = normal)
    • Verify SA bus power and wiring
    • Check EOL resistor placement
    • Inspect for duplicate SA addresses
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0 – NAE LED status indicators, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-025 — MS/TP Token Pass Failure
    Warning

    NAE BACnet MS/TP trunk unable to pass token — no controllers communicating. FC LED shows steady green.

    Likely Causes
    • All MS/TP controllers offline or unpowered
    • Bad termination causing token loss
    • Duplicate MAC address on MS/TP segment
    • Wiring open circuit
    First Checks
    • Check MS/TP wiring continuity
    • Verify 120-ohm terminators at ends
    • Confirm all controllers powered
    • Check for duplicate MS/TP addresses
    • Use NAE diagnostic tab to view trunk status
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0 – FCA LED descriptions, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-026 — Ethernet Link Down
    Shutdown

    NAE Ethernet port has no link — ETHERNET LED is steady off.

    Likely Causes
    • Ethernet cable disconnected or failed
    • Network switch port disabled or failed
    • IP address conflict causing NIC to disable
    • Physical port on NAE damaged
    First Checks
    • Verify Ethernet cable connection at both ends
    • Check switch port LED
    • Try a different cable or switch port
    • Ping NAE from PC on same subnet
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0 – ETHERNET LED status, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-027 — BACnet Object Event State – Fault
    Warning

    BACnet object's Event_State is set to FAULT (value=1) indicating the object Reliability property has reported a non-normal state.

    Likely Causes
    • Reliability = NoSensor, OverRange, UnderRange, OpenLoop, ShortedLoop, or CommunicationFailure
    • Sensor wiring issue
    • Remote object communication lost
    First Checks
    • Read object Reliability attribute in SCT
    • Check sensor wiring and signal range
    • Verify BACnet network connectivity
    Source: Metasys SMP Help LIT-1201793 v14.0 – BACnet Alarm Tab / Event State, docs.johnsoncontrols.com; BACnet ASHRAE 135
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-028 — BACnet Object Event State – OffNormal
    Warning

    Binary or multistate object's Present Value entered a configured Alarm Value state.

    Likely Causes
    • Equipment fault bit active
    • Safety input tripped
    • Binary status indicating abnormal state
    First Checks
    • Identify which Alarm Value was triggered
    • Check physical equipment status
    • Review alarm value configuration
    Source: Metasys SMP Help LIT-1201793 v14.0 – BACnet Alarm Tab, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-029 — BACnet Object Event State – High Limit
    Warning

    Analog object Present Value exceeded High Limit threshold set in BACnet intrinsic alarming.

    Likely Causes
    • Process variable too high
    • Sensor calibration drift high
    • High Limit set too low in configuration
    First Checks
    • Check actual physical value
    • Calibrate sensor
    • Review High Limit setting
    Source: Metasys SMP Help LIT-1201793 v14.0 – BACnet Alarm Tab / Event State options, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-030 — BACnet Object Event State – Low Limit
    Warning

    Analog object Present Value dropped below Low Limit threshold set in BACnet intrinsic alarming.

    Likely Causes
    • Process variable too low
    • Sensor failure
    • Low Limit too high in configuration
    First Checks
    • Check actual physical value
    • Verify sensor signal
    • Review Low Limit setting
    Source: Metasys SMP Help LIT-1201793 v14.0 – BACnet Alarm Tab, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-031 — Life Safety Alarm
    Shutdown

    A BACnet Life Safety object (e.g., smoke detector, sprinkler flow) has transitioned to an alarm state.

    Likely Causes
    • Smoke/fire condition detected
    • Sprinkler flow activated
    • Life safety device fault
    • Manual pull station activated
    First Checks
    • Immediately investigate life safety condition
    • Check physical life safety device status
    • Confirm with fire alarm panel
    • Do not reset until cause is identified
    Source: Metasys SMP Help LIT-1201793 v14.0 – Alarm Type Life Safety Alarm, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-032 — Metasys Alarm Value Enum – FAU (Fault)
    Warning

    Metasys internal Alarm Value Enumeration value 1 = FAU indicating a fault condition on the point.

    Likely Causes
    • Object reliability issue
    • Input out of range
    • Communication loss to source
    First Checks
    • Read Reliability attribute
    • Check physical wiring
    • Verify communication path
    Source: Metasys Appendix A Object Enumeration Sets LIT-694980 Table A-16, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-033 — Metasys Alarm Value Enum – OFN (Off Normal)
    Warning

    Metasys internal Alarm Value Enumeration value 2 = OFN — object is in Off-Normal alarm state.

    Likely Causes
    • Binary alarm point in active/alarm state
    • Multistate value in alarm state
    • Process variable outside normal range
    First Checks
    • Identify which point triggered OFN
    • Check physical equipment status
    Source: Metasys Appendix A Object Enumeration Sets LIT-694980 Table A-16, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-034 — Metasys Alarm Value Enum – HL (High Limit)
    Warning

    Metasys internal enum value 3 = HL — analog point is in High Limit alarm state.

    Likely Causes
    • Process variable above high limit
    • Sensor reading high
    First Checks
    • Review actual process value
    • Check sensor calibration
    Source: Metasys Appendix A Object Enumeration Sets LIT-694980 Table A-16, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-035 — Metasys Alarm Value Enum – LL (Low Limit)
    Warning

    Metasys internal enum value 4 = LL — analog point is in Low Limit alarm state.

    Likely Causes
    • Process variable below low limit
    • Sensor failure
    First Checks
    • Review actual process value
    • Check sensor wiring
    Source: Metasys Appendix A Object Enumeration Sets LIT-694980 Table A-16, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-036 — Metasys Alarm Value Enum – ALM (Alarm)
    Warning

    Generic alarm state (enum 68) for binary alarm objects.

    Likely Causes
    • Equipment alarm state active
    • Binary sensor in alarm position
    First Checks
    • Identify source point and check physical equipment
    Source: Metasys Appendix A Object Enumeration Sets LIT-694980 Table A-16, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-037 — Metasys Alarm Value Enum – SHT (Shutdown)
    Shutdown

    Object alarm state indicates equipment shutdown (enum 72 = SHT).

    Likely Causes
    • Equipment protective shutdown activated
    • Safety interlock tripped
    First Checks
    • Check equipment fault indicators
    • Verify safety interlock status
    Source: Metasys Appendix A Object Enumeration Sets LIT-694980 Table A-16, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-038 — Metasys Alarm Value Enum – UNR (Unreliable)
    Warning

    Object alarm state is Unreliable (enum 73 = UNR) — sensor or communication issue.

    Likely Causes
    • BACnet Reliability not NO_FAULT_DETECTED
    • Sensor disconnected
    • Communication failure
    First Checks
    • Read Reliability attribute
    • Check sensor wiring
    • Verify network path
    Source: Metasys Appendix A Object Enumeration Sets LIT-694980 Table A-16, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-039 — Metasys Alarm Value Enum – OFL (Offline)
    Warning

    Object alarm state is Offline (enum 71 = OFL) — device or object is unreachable.

    Likely Causes
    • Field device communication loss
    • Device powered down
    • Bus wiring failure
    First Checks
    • Check device power and communication LEDs
    • Inspect bus wiring
    Source: Metasys Appendix A Object Enumeration Sets LIT-694980 Table A-16, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-ALM-040 — Alarm Flags Enum – Irregular Action (1)
    Warning

    Output object performed an unexpected or irregular action relative to command.

    Likely Causes
    • Output wiring fault
    • Actuator slipping or seized
    • Control logic error
    First Checks
    • Check output wiring
    • Verify actuator operation
    • Review control logic
    Source: Metasys Appendix A Object Enumeration Sets LIT-694980 Table A-14 – Alarm Flags Enumeration Set, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-DIAG-001 — NAE Power LED Off
    Shutdown

    NAE not receiving 24 VAC power or battery backup — unit is shut down.

    Likely Causes
    • 24 VAC transformer failure
    • Power supply wiring fault
    • Tripped circuit breaker
    • Battery backup depleted
    First Checks
    • Check 24 VAC at power terminals
    • Verify transformer output
    • Check circuit breaker
    • Replace battery if applicable
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0 – POWER LED table, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-DIAG-002 — FEC/MEC Communication Fault on FC Trunk
    Warning

    A Field Equipment Controller or Modular Equipment Controller is not responding on the FC bus (MS/TP or N2).

    Likely Causes
    • FEC/MEC unpowered
    • Bus wiring fault
    • Incorrect EOL termination
    • FEC address conflict
    • Failed controller
    First Checks
    • Check FEC/MEC power LED
    • Inspect FC bus wiring
    • Verify EOL switch positions
    • Check for duplicate addresses in SCT
    Source: Metasys Field Equipment Controllers Product Bulletin, Johnson Controls; NAE Commissioning Guide LIT-1201519
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-DIAG-003 — ADX/ADS Communication Failure
    Warning

    NAE/SNE cannot reach the site's ADS/ADX server — event forwarding suspended.

    Likely Causes
    • ADS/ADX server offline or rebooting
    • Network switch failure
    • IP address misconfiguration
    • Firewall blocking BACnet/TCP port
    First Checks
    • Ping ADS/ADX server from NAE subnet
    • Check ADS/ADX Windows service status
    • Review network firewall rules
    • Verify ADS/ADX IP in NAE configuration
    Source: Metasys SNE Commissioning Guide LIT-12013352 v15.0, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-DIAG-004 — Invalid Object ID (BACnet Server Fault Cause)
    Warning

    Metasys BACnet local device object ID is invalid — BACnet server shows {fault} status above the Object Id field.

    Likely Causes
    • Device instance number set to default/invalid value (-1)
    • Duplicate device instance on BACnet network
    • Configuration not saved after IP setup
    First Checks
    • Set Device Instance to a unique positive value
    • Confirm no duplicate device IDs on network
    • Save configuration and verify Status changes to {ok}
    Source: NiagaraAX-3.x BACnet Guide, Cochrane Supply (Tridium); applicable to Metasys BACnet server setup
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-DIAG-005 — BACnet Server Capability Not Licensed
    Warning

    Metasys device is attempting to export BACnet objects but BACnet server license is not installed or enabled. Export descriptors show 'fault status' with cause 'Server capability not licensed'.

    Likely Causes
    • BACnet server license not purchased or installed
    • License server unreachable
    • License expired
    First Checks
    • Check Metasys software license inventory
    • Verify license server connectivity
    • Contact JCI for license activation
    Source: NiagaraAX-3.x BACnet Guide (applies to Metasys BACnet server export), Cochrane Supply
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-NET-001 — SNMP Trap Send Failure (DDA)
    Warning

    Metasys Data Delivery Agent (DDA) failed to send SNMP trap to configured SNMP management system.

    Likely Causes
    • SNMP server IP address incorrect
    • UDP 162 blocked by firewall
    • SNMP community string mismatch
    • SNMP server offline
    First Checks
    • Verify SNMP destination IP in NAE configuration
    • Check network firewall for UDP 162
    • Confirm SNMP community string matches server
    • Ping SNMP server from NAE subnet
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0 – DDAs overview, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-NET-002 — Email DDA Send Failure
    Information

    Metasys email notification failed to send via SMTP.

    Likely Causes
    • SMTP server address incorrect
    • Port 25/587 blocked by firewall
    • Authentication credentials wrong
    • Recipient email address invalid
    First Checks
    • Verify SMTP server address and port in NAE DDA
    • Check firewall rules for outbound SMTP
    • Test credentials on SMTP server directly
    • Confirm recipient email validity
    Source: Metasys NAE Commissioning Guide LIT-1201519 v11.0 – DDAs, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-BAC-001 — BACnet Duplicate Device ID Detected
    Warning

    Two or more devices on the BACnet internetwork share the same Device Object Instance number.

    Likely Causes
    • New device added with default or copied ID
    • Controller cloned without changing ID
    • Integration of devices with pre-configured IDs
    First Checks
    • Use SCT or Workbench to scan for duplicate IDs
    • Identify both devices and change one
    • Verify all device IDs are unique site-wide
    Source: NiagaraAX-3.x BACnet Guide – Bacnet Device Find; Metasys SCT Help LIT-12011964, docs.johnsoncontrols.com
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-BAC-002 — BACnet Network Number Conflict
    Warning

    Two network ports on the same BACnet internetwork have the same Network Number, causing routing failures.

    Likely Causes
    • Multiple MS/TP trunks assigned Network Number 1 by default
    • New NAE added with same network number as existing
    • BBMD configuration error
    First Checks
    • Verify all BACnet network numbers are unique across site
    • Check Bacnet Comm Network Number in NAE configuration
    • Valid range is 1-65534
    Source: NiagaraAX-3.x BACnet Guide – About Bacnet Comm, Cochrane Supply; Metasys BACnet implementation
    Johnson Controls Metasys · NAE35/45/55/85, NCE25, SNC, SNE, ADX/ADS Server, FEC/MEC/FAC
    MET-BAC-003 — MS/TP Lost Token
    Information

    Token was lost on an MS/TP segment. The device with the lowest MAC address regenerates the token.

    Likely Causes
    • Transient noise on RS-485 bus
    • Bad termination resistor
    • Failing device dropping off bus momentarily
    • Long cable run exceeding spec
    First Checks
    • Check cable length and routing
    • Verify termination at both ends
    • Inspect for EMI sources near cable run
    • Test each device individually
    Source: NiagaraAX-3.x BACnet Guide – MS/TP Address note, Cochrane Supply
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