Gent S4 CO Dual Optical Heat Sensor
| Part no. | S4-901 |
|---|---|
| Brand | Gent |
| Range | S4 Detectors |
| Sub-range | Detectors Only |
Image for illustration; item supplied may differ
At a glance
- Dual optical, heat and CO sensorDual-angle optical chamber, thermistor and carbon monoxide cell. Sensing readings are sent to the control panel.
- 9 selectable sensing modesSTATE 0: normal optical, Class A1 heat and normal CO sensitivity. The response is selected during commissioning.
- CO fire indicationA blue LED indicates CO in a fire signal, alongside the red fire LED.
- Integral short circuit isolatorThe head includes loop short circuit isolation. S-Quad devices take their power from the loop at 35 V to 48 V.
- S-Quad mounting optionsFits the separate S4-700 base; the S4-FLUSH kit supports semi-flush mounting for white S-Quad heads.
- Nano loop loadingNano load factor 0.5 per device. The Nano panel limit is 127 devices on its loop, subject to loop loading.
Description
The Gent S4-901 is an addressable dual optical, heat and CO sensor for Vigilon Plus, Compact Plus and Nano fire alarm panels. It combines smoke readings at two angles with a heat element and a carbon monoxide cell for fire detection. Nine sensing modes are selectable, with normal optical and CO sensitivity plus Class A1 heat as the default. A blue LED indicates CO in a fire signal, alongside the red fire LED. The head is loop powered, includes a short circuit isolator and fits the separate S4-700 base. The CO element typically lasts five to seven years; replace the sensor at the end of that period.
The S4-901 combines dual-angle optical smoke sensing, thermistor heat sensing and a carbon monoxide cell. Its sensing channels are 1 for forward optical, 2 for heat, 3 for CO and 4 for backward optical. The CO element detects gas from carbon-based smouldering fires, contributing to the fire decision alongside the smoke and heat readings in the default mode. This sensor head has no integral sounder, voice output or visual alarm device. A version with a voice sounder and a High Power visual alarm device is ordered separately as S4-911-V-VAD-HPR (red) or S4-911-V-VAD-HPW (white).
Read the full technical description
The S4-901 combines dual-angle optical smoke sensing, thermistor heat sensing and a carbon monoxide cell. Its sensing channels are 1 for forward optical, 2 for heat, 3 for CO and 4 for backward optical. The CO element detects gas from carbon-based smouldering fires, contributing to the fire decision alongside the smoke and heat readings in the default mode. This sensor head has no integral sounder, voice output or visual alarm device. A version with a voice sounder and a High Power visual alarm device is ordered separately as S4-911-V-VAD-HPR (red) or S4-911-V-VAD-HPW (white).
Nine sensing STATEs are selectable: 0, 1, 2, 4, 6, 7, 9, 11 and 12. STATE 0 combines normal optical sensitivity, Class A1 heat and normal CO sensitivity. STATE 1 raises both optical and CO sensitivity while retaining Class A1 heat. STATE 12 provides Class A1 heat-only detection. The selected STATE determines which sensing elements contribute to the fire decision; the different modes do not all use every element.
The red LED indicates fire, and a separate blue LED indicates CO in a fire signal. S-Quad devices monitor their sensing circuits for faults, including the CO cell circuit on CO models. The CO cell has an expected life of five to seven years; replace the sensor at the end of that period. For this CO head the storage range is -20°C to +50°C, while its operating range is -10°C to +50°C.
S-Quad devices take power from the loop at 35 V to 48 V. This head includes a short circuit isolator. Its Nano load factor is 0.5; Nano allows a maximum of 127 devices on its loop. This maximum is subject to loop loading. Use the Battery Standby and Loop Load calculator to determine the installed device mix, cable length and standby requirement.
S-Quad heads plug into the separately ordered S4-700 base. Mount the base on a metal back box, maintain loop earth continuity and connect earth securely to the box. The base locking peg can secure the head against removal. A locked head needs access to the peg for release. The S4-FLUSH kit provides semi-flush ceiling mounting for the white S-Quad range.
Use Vigilon commissioning tool version 1.32 or later for device-setting changes. The S-Quad programmable connection supports either a monitored input or an unmonitored output. The default output drives a remote repeat LED without a series resistor. One 13449-01 or SEN-LED remote indicator can connect to a base, with a maximum run of 15 m to the external I/O unit. The head is supplied with a dust cover, which must be removed before commissioning.
Specifications
| Device type | Addressable dual optical, heat and CO sensor |
|---|---|
| Sensor marking | O2HCO |
| Sensing elements | Dual-angle optical chamber, thermistor and carbon monoxide cell |
| Analogue sensing channels | 1: forward optical; 2: heat; 3: CO; 4: backward optical |
| Selectable sensing STATEs | 0, 1, 2, 4, 6, 7, 9, 11, 12 |
| Factory default | STATE 0: normal optical, Class A1 heat and normal CO sensitivity |
| Compatible panels | Gent Vigilon Plus, Compact Plus and Nano |
| Power source | Loop powered |
| S-Quad loop operating voltage | 35 V to 48 V |
| Nano load factor per device | 0.5 |
| Nano panel loop limit | 127 devices maximum, subject to loop loading |
| Short circuit isolator | Integral |
| S-Quad isolator voltage data | Vmax 48 V; Vnom 40 V; Vmin 35 V; Vso max 16 V; Vso min 8 V |
| S-Quad isolator current and impedance | IC max 0.8 A; IS max 1.25 A; IL max 50 microamps; Zc max 0.13 ohm |
|---|---|
| S-Quad head dimensions | 117 mm diameter x 49.6 mm high |
| S-Quad height with standard base | 63.8 mm |
| S-Quad housing | ABS; white RAL 9010 |
| S-Quad operating temperature | -10°C to +50°C |
| S-Quad CO storage temperature | -20°C to +50°C |
| S-Quad relative humidity | 95% non-condensing at +5°C to +45°C |
| Mounting base | S4-700, ordered separately |
| S-Quad programmable connection | Monitored input or unmonitored output; default remote LED output |
| S-Quad external I/O cable limit | 15 m from base to external I/O unit |
| CO cell life expectancy | Five to seven years; then replace the sensor |
| Fire indicators | Red fire LED; blue LED for CO in a fire signal |
Specifications per manufacturer documentation, subject to change. E&OE.
Documents
| Document | Type | Size | Download |
|---|---|---|---|
| Gent 4188-1073 issue 7 - S-Quad data and installation (white and black) | Installation | 7.2 MB | Download PDF |
Optional accessories
- S4-FLUSHS-Quad Semi-Flush Mounting KitWhite non-VAD/Sounder S-Quad can be semi-flush mounted with the S4-FLUSH kit£28.23ex VAT£33.88 inc VATIn stock
FAQs
What does the CO element add to the S4-901?
The S4-901 adds a carbon monoxide sensing cell to dual optical smoke and thermistor heat sensing. The CO cell detects gas associated with carbon-based smouldering fires. In the factory default STATE 0, normal CO sensitivity works alongside normal optical sensitivity and Class A1 heat. Its sensing channels are 1 for forward optical, 2 for heat, 3 for CO and 4 for backward optical. The head provides fire sensing without an integral sounder, speech output or visual alarm device.
How long does the CO cell in the S4-901 last?
Plan to replace the S4-901 sensor after the CO cell’s expected working life of five to seven years. The S4-901 combines that cell with dual optical smoke sensing and a thermistor, so the replacement concerns the sensor head. S-Quad devices monitor their sensing circuits for faults, including the CO cell circuit on CO models. The S4-901 fits the separate S4-700 base, takes power from the panel loop and includes a short circuit isolator within the head.
Do all S4-901 sensing modes use optical, heat and CO together?
The sensing combination depends on the selected STATE. The S4-901 offers nine options: 0, 1, 2, 4, 6, 7, 9, 11 and 12. Factory default STATE 0 uses normal optical sensitivity, Class A1 heat and normal CO sensitivity. STATE 1 raises optical and CO sensitivity while keeping Class A1 heat. STATE 12 gives Class A1 heat-only detection. The head retains its optical chamber, thermistor and CO cell, while the commissioning selection determines which sensing elements contribute to the fire decision.
What does the blue LED on the S4-901 indicate?
The blue LED indicates CO in a fire signal. It sits alongside the red LED used for fire indication on S-Quad heads. The S4-901 combines a CO sensing cell with dual optical and heat sensing, and its factory default mode uses all three sensing technologies. The optical readings reach the panel on channels 1 and 4, heat on channel 2 and CO on channel 3. The blue LED is an indication on this sensor head, which has no integral sounder or voice output.
Which base and loop loading apply to the S4-901?
The S4-901 fits the separately ordered S4-700 base. On Nano, its load factor is 0.5 per device, with a maximum of 127 devices on the loop subject to loop loading. Use the Battery Standby and Loop Load calculator for the installed device mix, cable length and standby requirement. The head takes power from the loop and includes a short circuit isolator. S-Quad devices operate at 35 V to 48 V. The S4-901 combines dual optical, heat and CO sensing.