The Polytron IR was a permanent gas detector for monitoring combustible gases using a Infra red sensor. Two choices were available, firstly type 340 which opened the door to new applications picking up alkanes and cyclohexane. Configurable from 5 to 100 %LEL. Or secondly type 334 measuring 0 to 20 %LEL and up to 100 %LEL, alternatively 0 to 100 %v/v for methane. The IR sensor had a longer life span and was robust allowing use in harsh conditions such as offshore. Little maintenance was required and drift free less than 2% LEL.
The detector sent a 2 mA signal to the controller in the event of dirty optics, allowing preventive measures and continued readings before a block beam signal at less than 1mA was generated. Normal output signal 4-20mA. HART and RS485 digital outputs were provided.
Those currently in operation are permitted for use in hazardous areas and have the following approvals UL, CSA Class 1, Div 1, Groups B, C, D, ATEX.
Transmitter housing SS316 stainless steel.
Polytron IR Part Numbers
UL Type 334 6810098
CEN Type 334 6810100
CEN Type 334 complete set 8315629
UL Type 340 6810820
CEN Type 340 6810760
CEN Type 340 complete set