Interfaces
A fire alarm interface unit connects a fire alarm loop to equipment outside the alarm system. Its output relay switches a control circuit, so the panel can drive plant, an AOV controller, a lift controller or door release. Its monitored input brings a contact signal back to the panel, from a sprinkler flow switch or a plant status contact. Confirmation pairs the two, and the panel then watches for the equipment's response to its own command. We stock Gent S4 interfaces, Morley-IAS addressable interface modules, VESDA remote modules, conventional modules and relays, and intrinsically safe Zener barriers. Our guide, What can a fire alarm interface switch?, works through each duty and names the part for it.
Gent interface modules powered by the loop for Vigilon, Compact Plus and Nano systems sit in S4 Interfaces and Accessories. It covers inputs, changeover relay outputs, mains switching and mains powered units, plus enclosures, DIN brackets and spare boards. Many carry LPCB approval to EN 54-17 and EN 54-18.
- S4 Interfaces & Accessories
21 products
S4 Interfaces and Accessories covers single and multi-channel input/output interfaces, including LV interfaces, supervisory input modules, relay interfaces and single and four-channel mains switching interfaces, with and without enclosures.
Conventional Modules and Relays is where we list fire alarm relay modules and timers for conventional systems. It holds a 24V DC double pole changeover relay with its enclosure, and an octal base timer. A DIN rail enclosure houses relay and timer modules. One power relay serves the 32440 mains powered interface unit.
- Conventional Modules & Relays
7 products
Conventional modules and relays, including 24V DC DPCO and base relays with diode, a timer with octal base, and a DIN-rail high profile enclosure.
Zener Barrier holds the two Gent Zener barriers we stock for intrinsically safe circuits. The Z969 protects intrinsically safe detection circuits and is used within the Gent S4 mains powered interface unit. The Z779 barrier drives intrinsically safe alarms.
- Zener Barrier
2 products
Zener barriers for intrinsically safe Gent systems, supplied via the Z-System.
Addressable Interface modules covers M200 series Morley interface modules that monitor and control auxiliary equipment on a Morley addressable loop. Input, output, relay and conventional zone modules are here, with surface boxes and DIN brackets. The M201EA-240 module is loop powered and complies with EN 54-17 and EN 54-18.
- Addressable Interface modules
21 products
The Addressable Interface Modules range provides input (monitor), output (relay control) and combined input/output modules for interfacing addressable systems with contact devices such as flow switches, security contacts and plant outputs.
Choose by the signals the equipment needs. For one monitored input, we supply S4-34410. For an output on its own, the S4-34411 fire alarm relay module gives a DC changeover relay in a DIN rail format. S4-34420 pairs an output relay with a monitored input for confirmation. S4-34450 gives four channels, each configured as an input or an output. For mains switching, S4-34401 controls one circuit and S4-34404 controls four, through 16A 250V contacts. S4-34440-02 and S4-34440-12 are mains powered and supply 24V sector outputs. Morley addressable interface modules sit on a Morley-IAS loop, and VESDA remote modules serve VESDA aspirating detection.
Frequently asked questions
- Can a fire alarm panel open an AOV?
- The panel does not open the vent itself. An interface passes its instruction to a compatible AOV controller, and that controller opens the vent. We supply S4-34420 where its changeover contact, rated 1A at 30V AC/DC resistive, matches the controller. Its monitored input takes a return contact for confirmation. The module needs a separate enclosure, and we recommend the S4-34492 metal box. Tell us the trigger and return signals with your Gent panel details.
- Do I need a monitored input for a sprinkler flow switch?
- Yes. We supply S4-34410 for the flow contact, on a monitored circuit that detects open and short circuits. It accepts normally open or normally closed contacts and has no output channel. Its fire-input acceptance delay extends to ten seconds. BS 5839-1 requires a hydraulic or electronic delay where pressure surges risk unwanted alarms. The module takes its power from the Gent loop and needs a separate enclosure.
- What is a confirmation input?
- Confirmation pairs a return contact with an output. The panel looks for the equipment's response within a defined time. It raises a fault if the expected contact change does not arrive. We supply S4-34420 with that relay and input, and S4-34450 pairs separate channels for the same duty. S4-34410 monitors fire, fault or supervisory contacts, but it has no output and no confirmation function.