SMA SSM8-21-BS - Manual (Page 48)

10 Maintenance SMA Solar Technology AG
48 SSMxx-21-IA-BS-JP-en-20 Installation Manual
10.11 Checking the Surge Arrester for RS485 Communication
In device type SSMxx-21-BS-JP, there is a surge arrester for RS485 communication installed.
Additionally required material (not included in the scope of delivery):
☐ Measuring device DEHNrecorder LC M3
☐ Measuring device PM20
☐ Test adapter PA BXT
Procedure:
2. For the surge arrester BVT ALD 60, use the measuring device PM20 3 to perform the measurements (see
documentation of the measuring device). Check whether the readings are within the tolerance range defined by the
lower threshold LLV and the upper threshold ULV:
If the readings are outside the tolerance limits, replace the surge arrester.
3. For the module BXT ML2 BD, use the measuring device PM20 3 to perform the measurements (see documentation
of the measuring device). Check whether the readings are within the tolerance range defined by the lower threshold
LLV and the upper threshold ULV:
If the readings are outside the tolerance limits, replace the surge arrester.
10.12 Checking the Supply Voltage
Required maintenance material (not included in the scope of delivery):
☐ Voltmeter
Requirement:
☐ The circuit breaker for the supply voltage of the Sunny Central must be switched on.
Procedure:
2. Measure the supply voltage at the connector on the lowest String-Monitor Unit.
☑ The supply voltage is at least 30 V.
✖ The supply voltage is less than 30 V?
1. '$1*(5
Danger to life by electric shock or electric arc if live components are touched
• Disconnect the Sunny String-Monitor from voltage sources (see Section 8, page 41).
Measurement 1 Measurement
2
Measurement 3
LLV 0 V 73 V 0 V
ULV 219 V 83 V 1 V
Measurement 1 Measurement
2
Measurement 3
LLV 182 V 17 V 0 V
ULV 279 V 22 V 1 V
1. '$1*(5
Danger to life by electric shock or electric arc if live components are touched
• Disconnect the Sunny String-Monitor from voltage sources (see Section 8, page 41).