QED MicroPurge basics MP10UH Instruction Manual page 20

Operation
The MP10UH and MP30 are connected with a cable (see Figures 6 and 7). The MP30 is
switched into mode and the water level probe is lowered to the desired maximum draw-
down level. Limiting the maximum drawdown depth limits the differential head driving flow
into the well and the velocity of the water flowing into the well from the surrounding formation
important in MicroPurge sampling. The MP10UH and MP30 work together to automatically
adjust the pump operation so as to maintain drawdown at the set level. When the water level
drops below the probe, the MP30 sends a signal to the MP10UH to pause pumping. Both the
MP10UH and the MP30 give visual signals (and the MP30 emits an audio signal) that pump
operation has stopped because of too much drawdown. Once the level recovers, the MP30
signals the MP10UH to resume pump operation. The MP10UH resumes by starting in the refill
leg of the pump cycle. "DRAWDOWN CONTROL"
The normal operating mode for using the MP30 with the MP10UH is:
1. Use the MP30 in standard WLM mode to determine the static water level in the well
2. Decide what the maximum drawdown for that well is during sampling
3. Lower the probe to the maximum drawdown level
4. Switch the MP30 into Drawdown Control mode
5. Begin pumping with the MP10UH
6. Observe the interactions between the two devices, if the MP30 is frequently pausing the
MP10UH, it may be appropriate to slow the flow down (using the DOWN key in MP mode)
to better match pump flow to well recharge.
When switched into MODE, the MP30 has a flashing red light and an optional (can be switched
off by the user) audio alarm to indicate when the probe is in the dry state. A submerged probe
in all modes is indicated by a solid green light. When the MP10UH is paused by the MP30 the
MP10UH display indicates this as shown in Figure 5."DRAWDOWN CONTROL"
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