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Hydra 256

Addressable car park gas detection system



Hydra allows a connection of a maximum of 256 detectors to a single panel via addressable RS-485 loops.

Features include:

  • Able to control up to 256 remote outputs, all of which are programmable
  • Built-in relays can be used to indicate the system status remotely or provide control of auxiliary equipment
  • Modbus RTU output for connection to Building Management Systems (BMS)
  • Event log functions
  • Optional battery back up

Contact [email protected] for more information.



    Hydra256 Hydra+
Size   430W x 405H x 140D mm (16.9x16x5.5 ins)  100W x 180H x 65D mm (3.9x7x2.5 ins)
Weight   7.9Kg (17.4lbs) 0.4kg (0.9lbs)
Enclosure material   Painted steel Painted alloy
Ingress protection   N/A IP55
Operating temperature 0 to +55°C (32 to 131°F) -10 to +55°C (14 to 131°F)
Storage temperature -20 to +60°C (-4 to 140°F)
Humidity 15-85%RH non-condensing 20-90%RH non-condensing (RH @40°C)
Battery back-up   2 x 12V 7Ah lead-acid batteries (optional) N/A
Inputs   Up to 256 addressable Hydra+ gas detectors. Two RS-485 buses supplied (max. 128 detectors), two extra buses may be added N/A
Outputs   3 x alarm relays (alarm level 1,2,3)
1 x fault relay
1 x power fail relay
1 x battery relay
1 x sounder relay
1 x test relaySPCO contacts rated 16A 230Vac
RS-485 Modbus
Addressable output modules   One to four 16-way modules can be connected per RS-485 bus to provide up to 64 additional open-collector outputs, or up to 64 SPCO relays when used with 8-way relay modules. 256 outputs maximum N/A
  Relays can be energised/de-energised, latched/non-latched, time-delayed, pulsed. Contacts rated 16A 230Vac
Digital communications   RS-232 port for system configuration via a PC (software and lead supplied), or for Modbus communication to BMS/DCS/PLC systems. N/A
Event logging   Up to 1000 alarm, power, fault, system events are stored in NVM and on SD card. N/A
Panel indication   Graphic LCD
6 x red Alarm (alarm level 1,2,3)
2 x yellow Fault
2 x yellow Over-range
2 x yellow Under-range
2 x green Power/battery
2 x yellow Inhibit/test
Gases and ranges     CO: 0-300ppm
NO2 : 0-20ppm LPG/Propane: 0-100% LEL
Sensor life     4 years typical
Approvals   EMC: EN50270, EN61000-6-3: 2001 + A11 (2004) N/A


Below is a small selection of the accessories available for the Crowcon Hydra 256. For a full list please call 01235 557700 or Contact Us.

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