Device-Specific Safety Instructions; Intended Use - Bender ISOMETER isoPV1685RTU Manual

2.3 Device-specific safety instructions

2.4 Intended use

The isoPV1685RTU and the isoPV1685P are used for insulation monitoring of large photo-
voltaic systems up to AC 1000V and DC 1500 V designed as IT systems. The measurement
method specially developed for slow voltage fluctuations (MPP tracking) monitors the in-
sulation resistance even in systems equipped with large solar generator panels where ext-
remely high system leakage capacitances against earth exist due to interference suppres-
sion methods. Adaptation to system-related high leakage capacitances also occurs auto-
matically.
The isoPV1685P generates locating current pulses required for insulation fault location.
That allows the localisation of the insulation fault using permanently installed or mobile in-
sulation fault locators.
Intended use also implies:
• The observation of all information in the operating manual
• Compliance with test intervals
In order to meet the requirements of applicable standards, the equipment must be adjus-
ted to local equipment and operating conditions by means of customised parameter set-
tings. Please heed the limits of the range of application indicated in the technical data.
Any other use than that described in this manual is regarded as improper.
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Installation inside a control cabinet
If the ISOMETER® is installed inside a control cabinet, the insulation fault
message must be audible and/or visible to attract attention.
IT systems with several ISOMETER®s
Make sure that only one active ISOMETER® is connected in each
interconnected system. If IT systems are interconnected via coupling
switches, make sure that ISOMETER®s not currently used are disconnec-
ted from the IT system and deactivated. For IT systems coupled via diodes
or capacitances a central control of the different ISOMETER®s is required.
Prevent measurement errors!
When a monitored IT system contains galvanically coupled DC circuits,
an insulation fault can only be detected correctly if the rectifier valves
(e.g. rectifier diode, thyristors, IGBTs, frequency inverters, ...) carry a
minimum current of > 10 mA.
Unspecified frequency range
When connecting to an IT system with frequency components below the
specified frequency range, the response times and response values may
differ from the indicated technical data. However, depending on the
application and the selected measurement method, continuous
insulation monitoring is also possible in this frequency range.
isoPV1685xxx_D00007_08_M_XXEN/03.2023
Safety instructions