HT PVCHECK, Manual

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PVCHECK 34
2. In case the instrument detects a voltage lower than 15Vat
terminals P and N, it does not carry out the test, gives out a long
sound
and displays the message “Low voltage”.
3. In case the instrument detects a voltage higher than > 5Vat
terminals E and C, it does not carry out the test, gives out a long
sound and displays the message “Voltage > Lim”.
4. In case the instrument detects an Isc current higher than 10A, it
does not carry out the test, gives out a long sound and displays
the message “Isc current too high”.
6.4. MEASUREMENT OF INSULATION ON PV MODULES/STRINGS/FIELDS (M
Ω
)
6.4.1. Foreword
The purpose of this function is to measure the insulation resistance of the active conductors of a
module, string, of a whole PV field and of possible unearthed metal masses according to the
prescriptions IEC/EN62446 guideline. In general, the instrument measures insulation in the
following modes:

FIELD mode

used for measuring insulation resistance of a PV field (photovoltaic generator)
consisting in one or more strings connected in parallel. The instrument performs the
measurement on the Positive and Negative poles of the PV field.

TIMER mode

the instrument measures continuously (with a max duration of 300s) on terminal
“P” only, displaying the minimum resistance value obtained at the end of the selected time. It
may be used for measuring the insulation resistance of more unearthed metal masses.

STRING mode

used for measuring insulation only on single PV modules or strings,
automatically creating an internal short-circuit between the Positive and Negative poles, with no
need to use an external switch to short-circuit the positive and negative terminals and measuring
between this short-circuit point and the installation earthing.