ABB PRO-33.0-TL Series, Service Manual

Page: 30 / 122

30 Program features
174.22 Blown fuse detection
174.23 Blown fuse tolerance
174.24 Blown fuse active boundary
174.50 Current: [1] -- 174.57 Current: [8]

String current deviation detection (-SX model)
A faulty string, for example, due to high amount of shadowing or obstacles can be
detected if the current in one string deviates significantly from other strings. The feature
can be enabled with parameter
174.14 String current detection and it has several
configuration parameters.
Inverter can be configured to use either relative or absolute comparison between string
currents with parameter
174.16 Comparison mode . If there is a major difference, a warning
is indicated after the delay set in parameter 174.15 String monitor delay . The value that the
individual currents are compared against is the reference value of which type is defined in
parameter
174.17 Reference type . The reference value can be selected to be either the
maximum or the mean value of the connected strings.
•
In absolute mode , individual string currents are compared against the reference
value in amperes. If the difference is greater than the value set in parameter 174.19
Absolute current limit in amperes, a warning is indicated after a delay.
•
In relative comparison mode , individual string currents are compared against the
reference value in percent. The limit is defined in parameter 174.18 Relative current
limit . If a string current is greater or lower than the reference value, a warning is
indicated after the delay time is elapsed. In addition, the reference value must be
greater than the value defined in parameter
174.20 Relative threshold to avoid
nuisance warnings at very low currents.
Settings
174.11 Input connection status
174.14 String current detection
174.15 String monitor delay
174.16 Comparison mode
174.17 Reference type
174.18 Relative current limit
174.19 Absolute current limit
174.20 Relative threshold
174.50 Current: [1] -- 174.57 Current: [8]