Hach-Lange SD900 User Manual - Manual (Page 17)

W A R N I N G
Electric shock hazard. The power supply can overheat when the time between pump cycles is too
short.
N O T I C E
Make sure that the pump cycle time will not cause the power supply to overheat. Refer to Calculate the pump
cycle time on page 15.
Connect the sampler to a battery or to an AC power supply. Refer to the illustrated steps that follow.
Calculate the pump cycle time
The pump must stay off for a minimum time period between sample cycles so that the power supply
does not overheat.
1. Calculate the total amount of time that the pump will run continuously during a sample cycle.
Include all stages: pre-purge, intake rinse, sample, sample retries and post-purge.
2. Find the minimum amount of time that the pump must stay off between sample cycles from
Figure 11 .
3. Make sure that the pacing or time interval in the sampler program lets the pump stay off between
sample cycles for the minimum amount of time.
English 15