Bacharach H25-IR Manual De Usuario

H25-IR 

Preparing for Operation 

 

Instruction 3015-4342 

17

 

 
 

 
 

 

 
 

The SEARCH AUTO ZERO function allows the operator to select one of the following conditions when the 

auto-zero function is disabled while in the Search mode: 

 This function works in conjunction with the setpoint value as entered in Section “2.5.5 Setpoint.” 

 – The background gas level is always zeroed. If the probe is held over a gas leak, the 

instrument will automatically zero-out the reading.  

 – The background gas level is never zeroed. If the probe is held over a gas leak, the 

instrument will not zero-out the reading, similar in operation to the Measure mode. 

 – The auto-zero function is ON when the leak-rate is below the setpoint value. If the 

leak rate goes above the setpoint value, then the auto-zero function turns OFF, allowing the probe to stay 
on the leak without the reading being zeroed-out. 

For example: If the Setpoint is 2 Oz/yr, then the auto-zero function is ON for leaks rates that are 
<2 Oz/yr. If the leak rate is ≥2 Oz/yr, then the auto-zero function turns OFF. 

 

 – The auto-zero function is ON when the leak-rate is below 90% of the setpoint value. 

If the leak rate goes above 90% of the setpoint value, then the auto-zero function turns OFF, allowing the 
probe to stay on the leak without the reading being zeroed-out.  

For example: If the Setpoint is 2 Oz/yr, then the auto-zero function is ON for leaks rates that are 
<1.8 Oz/yr. If the leak rate is ≥1.8 Oz/yr, then the auto-zero function turns OFF. 

 

 – The auto-zero function is ON when the leak-rate is below 75% of the setpoint value. 

If the leak rate goes above 75% of the setpoint value, then the auto-zero function turns OFF, allowing the 

probe to stay on the leak without the reading being zeroed-out.  

For example: If the Setpoint is 2 Oz/yr, then the auto-zero function is ON for leaks rates that are 
<1.5 Oz/yr. If the leak rate is ≥1.5 Oz/yr, then the auto-zero function turns OFF. 

 

 – The auto-zero function is ON when the leak-rate is below 50% of the setpoint value. 

If the leak rate goes above 50% of the setpoint value, then the auto-zero function turns OFF, allowing the 

probe to stay on the leak without the reading being zeroed-out.  

For example: If the Setpoint is 2 Oz/yr, then the auto-zero function is ON for leaks rates that are 
<1 Oz/yr. If the leak rate is ≥1 Oz/yr, then the auto-zero function turns OFF. 

 
 

The H25-IR has been calibrated at the factory, and should not require frequent calibrations when 

searching for gas leaks. When making measurements, however, the instrument should be calibrated on a 
periodic basis to ensure that it meets its published accuracy specification. 
 

Instructions on how to calibrate the instrument are contained in Section 3 Calibration. 
 

 

 

SEARCH AUTO ZERO 

SETUP NO.1 

        < 

ALWAYS ON 

 ALWAYS 

OFF 

 BELOW 

SETPOINT 

 

BELOW 90% OF SP 

 

BELOW 75% OF SP 

 

BELOW 50% OF SP