GST DI-M9301 Addressable Digital Single Input & Output Relay Module (UL Listed)

Description

The GST DI-M9301 Digital Single Input and Output Module is an intelligent, loop-powered addressable control and monitoring interface engineered for enterprise-grade fire detection, smoke management, and building automation systems. Combining an independently configurable dry contact relay output with a fully supervised input channel in a compact form factor, the DI-M9301 allows fire alarm control panels to simultaneously command external life safety plant equipment—such as fire dampers, smoke extract fans, elevator recalls, and door holders—while actively verifying contact closure confirmation signals from flow switches, pressure switches, or auxiliary limit contacts.

Technical Specifications Table

Microprocessor-Controlled Switching & Advanced AD Signal Sampling

The core intelligence of the GST DI-M9301 module lies in its built-in 8-bit processing architecture coupled with high-speed Analog-to-Digital (AD) sampling technology. Instead of relying on crude threshold triggers, the onboard processor continuously samples line voltage across the monitored input circuit, allowing the panel to instantly distinguish between a genuine contact actuation, an open-circuit wiring fault, or a direct line short. This high-resolution filtering suppresses transient line noise and electromagnetic interference (EMI) commonly encountered in industrial plant rooms, preventing costly false plant shutdowns and erroneous alarm dispatches.

Because the unit is powered directly from the communication loop, electrical installation workflows are simplified. Eliminating separate 24 VDC auxiliary field power runs reduces copper cabling requirements, lowers conduit congestion, and cuts panel power budget demands. The internal dry contact relay provides versatile Form-C switching capacity up to 2 Amps at 30 VDC, making it suitable for driving intermediate magnetic relays, triggering access control door strikes, stopping air handling units (AHU), or capturing elevator banks during primary alarm sequences.

Field programming and commissioning are achieved without the mechanical failure points associated with physical rotary dials or DIP switches. Installers assign individual loop addresses electronically using the GST P-9910B handheld programming tool. The module’s enclosure is engineered with an integrated clip rail base designed for tool-less snap-on attachment directly onto standard 35 mm DIN-Rail tracks inside modular automation enclosures, or secured via screw mounts inside standard electrical junction backboxes.

• Independent Dual Operation: The input detection circuit and output relay can be programmed to operate in tandem as an interlocked control-feedback loop or completely independent of one another.
• Dynamic AD Sampling: Continuously measures input line resistance against the 4.7 kΩ EOLR benchmark to isolate field wiring faults instantly.
• Field Programmable Electronic Memory: Non-volatile internal memory stores device addressing and parameter settings securely through power outages.
• Low Current Consumption: Draws an ultra-low standby current of ≤ 0.28 mA, maximizing total addressable device loading on extended SLC loops.

Frequently Asked Questions (FAQ)

Q1: What is the primary function of the GST DI-M9301 module?
A: The DI-M9301 serves a dual role: it provides a dry contact relay output to trigger external equipment (fans, dampers, relays) and includes a supervised input channel to monitor external dry contact equipment status (limit switches, water flow switches, tamper valves).

Q2: Does the GST DI-M9301 require an external 24 VDC auxiliary power supply?
A: No. The DI-M9301 is entirely loop-powered directly from the fire alarm signaling line circuit (SLC) operating between 16 VDC and 28 VDC.

Q3: How is the address assigned to this module during field installation?
A: Addressing is set electronically using the GST handheld programmer (P-9910B). This eliminates mechanical DIP switches and ensures stable addressing in vibrating environments.

Q4: What size End-of-Line Resistor (EOLR) is required for the input circuit?
A: The input monitoring loop requires a standard 4.7 kΩ (0.25 W) End-of-Line Resistor installed across the furthest contact terminals to detect open and short circuit faults.

Q5: Can the input port and output relay function independently?
A: Yes. The control panel can be programmed so that the input operates as an independent monitoring point while the relay operates under separate cause-and-effect matrix logic.

Q6: What is the maximum switching load capacity of the output relay?
A: The output relay is rated for resistive/inductive dry contact switching up to 2.0 Amps at 30 VDC (0.35 PF).

Q7: What mounting methods are supported by the GST DI-M9301 enclosure?
A: The module is designed with built-in slots for standard 35 mm DIN-Rail track mounting, and it can also be surface-mounted directly inside compatible deep electrical enclosures.