Environmental Sampling Unit 87 ESU    

There are many heavier than air gas monitoring applications where positioning of detectors is not practical for a variety of reasons. These may include the possibility of flooding, as in a wet well, or for monitoring large areas such as chlorine cylinder storage rooms where the only other option is multiples of sensors mounted at floor level. For these applications, Crowcon offers the 87 ESU Environmental Sampling Unit. 

The 87 ESU comprises two main components, the sampling chamber and the optional controller. Manufactured from high impact ABS, the chamber is fitted with an electric fan which draws air through the chamber and out to atmosphere. For monitoring flammable gases, an Ex m (encapsulated) fan is used. A gas detector is also fitted in the chamber, with its junction box mounted on the outside of the chamber. 

Connected to the chamber is a collection pipe with a maximum length of 12 meters. Two collection pipe with a maximum length of 12 meters. Two collection pipes can be used provided their combined length does not exceed 12 meters. Any right angle bends are equivalent to 2 meters of pipe length. These pipes can be open at the ends or have capped ends and be drilled with a series of holes along their length. Care should be taken with the size and location of the holes to ensure an efficient flow. For advice, contact Crowcon. 

For ease of installation, the system is supplied with a set of pipe fittings comprising 2 elbows, 2 end caps, 1 flange adaptor, 1 coupler and 6 pipe clamps. 

Because of the very low pressure developed by the unit, care must be taken with siting the pipes to ensure that extraneous pressure effects are eliminated, particularly in regard to wind and thermal currents with open ended pipes. 

The optional controller monitors the fan current from up to 5 units and includes relays for remote signaling of fan failure. 

In addition, units can be interfaced to Crowcon Gasmaster control panels by means of an interface card that allows the fan control circuit to connect to one of the Gasmaster input channels. In this way, two complete ESUs can be controlled by one Gasmaster 4. 

Features,

• Ideal for applications where flooding is a risk 
• One system can replace multiple detectors 
• Explosion proof fan option for hazardous area installation 
• Flexible pipe and flow configuration 
• Optional 5 channel controller for remote indication of fan fail 
• Capability to interface detectors and fan controls to Gasmaster panels.