SQFlex Service Instructions

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4.1.1 Trouble-shooting of a solar-powered system
1. Disconnect the pump
• Set the IO 50 switch to off.
• Disconnect the pump cable from the terminals (6T3, N, 8T4).
2. Check the solar modules
• Measure the voltage and short-circuit current across the terminals (2T1, 4T2).
See electrical connection in Section 1.4.
If the DC voltage or DC current is outside the range, one or more of the solar modules is faulty.
Replace the faulty solar module/s.
3. Check the IO 50 box
• Set the IO 50 switch to on.
• Measure the DC voltage across the terminals using a voltmeter.
• Measure the DC current through the wires using an ammeter.
If the values differ from the values measured under step 2, the IO 50 is defective.
Replace the IO 50 box.
4. Check the pump
• Set the IO 50 switch to Off.
• Reconnect the pump cable to the terminals.
• Switch on the pump by setting the IO 50 switch to On.
Note that the dry running sensor is covered with water.
If the pump starts, it was stopped due to dry running and has now been reset.
• Wait five minutes.
If the pump does not start, it is defective. Repair or replace the pump.
sqflex_SI_US_WG.book Page 28 Thursday, October 1, 2009 3:27 PM