What is the difference between the first and second generation Hach LDO sensor for Hydrolab sondes?

FAQ - Hach LDO™

1. Are first and second generation LDO sensors interchangeable?
2. Q: What is the difference between the first and second generation Hach LDO sensor for Hydrolab sondes?A: To the untrained eye, the first and second generation LDO sensors look very similar. The second generation sensor uses the same trusted and proven LDO measurement technology used in the first generation, only the sensor body and cap have been fortified. Illustrations of the first and second generation sensors are available in the Hach LDO instruction sheet for Series 5 Instruments (document number 00745589).
   
   
3. What is the recommended calibration procedure for Hach LDO?
4. What is Hach LDO and how does it work?
5. Is a circulator required with the Hach LDO sensor?
6. Will fouling affect the DO readings from a Hach LDO sensor?
7. How long will the sensor cap last?
8. What is the warranty on the Hach LDO sensor?