SMA STP 15000TL Service Manual - Manual (Page 31)

8 Checking the Function of the Varistors
Figure 2: Varistors inside the inverter
Destruction of the inverter due to overvoltage
If varistors are missing, the inverter is no longer protected against overvoltage.
• Do not operate the inverter without varistors in PV systems with a high risk of overvoltages.
• Do not recommission the inverter until the defective varistors have been replaced.
Destruction of the measuring device due to overvoltage
• Only use measuring devices with a DC input voltage range of 1,000 V or higher.
Check the function of each varistor as described in the following:
Procedure:
1.
Danger to life due to high voltages
• Disconnect the inverter from all voltage sources and open the lower enclosure lid (see
Section 2.2, page 7).
8 Checking the Function of the Varistors SMA Solar Technology AG
Service Manual 31 STP15-17TL-10-SG-en-10