Accurate continuous monitoring of oxygen in hydrogen / nitrogen atmospheres used in annealing furnaces

Supplier: Intelligent Systems Pty Ltd
14 October, 2021

The Novatech model 1738 Dew Point Transmitter provides in-situ measurement in annealing and other furnaces with protective atmospheres of hydrogen / nitrogen

The Novatech 1738 detects changes in the dew point of annealing furnaces allowing operators to take corrective action to prevent expensive re-work due to oxidation of the product. 

The Dew Point is calculated from the amount of oxygen measured in the furnace. The unique sensor manufactured by Novatech Controls uses a catalyst that attracts oxygen molecules in the same way as the surface of the steel does inside the furnace.

Using the Novatech 1738 is easy and convenient

• Simply enter the percentage of hydrogen used by the furnace
• Very low maintenance and re-calibration
• Two fully programmable isolated 4-20mA outputs
• Built in Modbus™ slave protocol and digital RS-485 networking

Dual sensors to provide redundancy to prevent costly shutdowns if a probe failure occurs

The Novatech 1738 Dew Point Transmitter accepts inputs from two sensors, averaging the two readings, or providing separate 4-20mA outputs for each sensor. In case of either one of the sensors failing, the transmitter warns the operator and locks onto the remaining sensor so that the
process can continue to operate.

The Novatech 1738 tells you what’s happening
Plant operators are alerted to failure of the probe by a plain English message on the transmitter’s LCD display. There are
30 probe and transmitter alarms, plus 4 alarms.

The upper line display indicates:

• Oxygen % – auto-ranging from 1 x 10-^30% to 100%

The lower line display can indicate any of the following:

• Dew point
• Pre-reactive oxygen %• Sensor EMF
• Probe temperature
• Probe impedance
• Ambient temperature
• Relative humidity
• Date/time
• Run hours