What does Positive Ground Fault mean on Simplex Fire Alarms?
- LLeslie Stewart PhDSep 12, 2025
If your Simplex Fire Alarms system indicates a Positive Ground Fault, it means a positive ground fault is present on the control unit.

What does Positive Ground Fault mean on Simplex Fire Alarms?
If your Simplex Fire Alarms system indicates a Positive Ground Fault, it means a positive ground fault is present on the control unit.
Why is my Simplex Fire Alarms showing AUX Power Trouble?
If your Simplex Fire Alarms system shows AUX Power Trouble, it means the battery voltage is less than 18 V.
What causes Charger Trouble in Simplex Fire Alarms?
If your Simplex Fire Alarms system reports Charger Trouble, it indicates that the voltage is less than 24 V and the charger is off.
What does City 1 Trouble mean on Simplex Fire Alarms?
If the Simplex Fire Alarms system displays 'City 1 Trouble', it means the city line 1 is disconnected, or there is a mismatch in the system option and physical status.
What does City 2 Trouble mean on Simplex Fire Alarms?
If the Simplex Fire Alarms system displays 'City 2 Trouble', it means the city line 2 is disconnected, or there is a mismatch in the system option and physical status.
What does DACT Phone Line 1 Trouble mean on Simplex Fire Alarms?
If your Simplex Fire Alarms system shows DACT Phone Line 1 Trouble, it means the control unit is unable to communicate by the DACT line 1.
What does EEPROM WRITE FAIL mean on Simplex Fire Alarms?
If your Simplex Fire Alarms system displays 'EEPROM WRITE FAIL', it means EEPROM write fail.
What does Negative Ground Fault mean on Simplex Fire Alarms?
If your Simplex Fire Alarms system indicates a Negative Ground Fault, it means a negative ground fault is present on the control unit.
Why does my Simplex Fire Alarms say Extra Card?
If your Simplex Fire Alarms system displays 'Extra Card', it means the annunciator connected to the control unit but not configured yet.
What does Card 4 Fail mean on Simplex Fire Alarms?
If your Simplex Fire Alarms system shows 'Card 4 Fail', it means communication is lost on card 4 for more than 10 seconds, or if card 4 is configured but not connected to the control unit.
| Brand | Simplex |
|---|---|
| Model | 2004 Series |
| Category | Control Unit |
| Language | English |
Details FCC compliance for digital devices, radio frequency energy, and potential interference in commercial environments.
Outlines reacceptance testing procedures required after any programming, software, hardware, or wiring modifications to ensure proper operation.
Explains the functions of the control unit's buttons like ACK, SILENCE, RESET, WALK TEST, and ENABLE/DISABLE for system operation.
Details the purpose and colors of various LEDs and the piezo sounder for status indication during different system conditions.
Describes the standard operating state of the control unit, including active LEDs and piezo status, when no events are present.
Explains how the system behaves and indicates a fire alarm condition, including LED flashing, piezo sounds, and relay activation.
Details the system's response and indications during a supervisory condition, such as LED flashing and piezo tone.
Describes the system's behavior and LED indications for various trouble conditions like AC loss, battery faults, or ground faults.
Lists the default function types assigned to Initiating Device Circuits (IDCs), Notification Appliance Circuits (NACs), and relays.
Outlines the default operating modes, such as steady or temporal, for NAC, relay, and signal circuit outputs.
Mentions the default settings for the Digital Alarm Communications Transmitter (DACT), including enabled status.
Details how to configure Initiating Device Circuits (IDCs) using DIP switches for function types like FIRE, SUPV, VSMOKE, or WSO.
Explains how to configure Notification Appliance Circuits (NACs) using DIP switches for function type, coding pattern, and EOLR selection.
Details how to configure the Digital Alarm Communications Transmitter (DACT) settings, including phone numbers and account numbers via PC tool.
Explains how to configure global system operations and hardware modules, such as time format and city circuit, via DIP switches.
Details how to activate and configure the walk test feature using control unit buttons and DIP switches for device functionality testing.
Specifies that the system time and date are set using the PC tool, not directly on the control unit.
Explains the process of transferring configuration job files between a service PC and the control unit.
Describes the procedures for performing warm start and cold start restarts of the control unit CPU using DIP switches and power cycles.
Lists system board troubles and their corresponding LED indications on the front panel and diagnosis LEDs for quick identification.
Explains the configuration of DIP switch SW1 for setting IDC function types for different zones (Zone 1-4).
Details the settings for DIP switch SW2, covering NAC function type, coding pattern, and feature enablement like Silence/Reset Inhibit.
Describes the settings for DIP switch SW3 related to NAC EOLR values, Class-A wiring configuration, and NFPA NAC features.
Outlines the settings for DIP switch SW4, covering annunciators, DACT, city circuit, reminders, AHJ Reset, and CPU restart options.