DANGER
Modified design of the DC inputs
The design of the DC inputs on the DC terminal
block has changed in comparison with previous
versions of the M88H_121 (ST)!
► You must comply with the correct use of plus
(+) and minus (-) when connecting the DC
cables.
The M88H_121 (ST) is designed by default for operation with
2 MPP trackers (MPPT). To accomplish this, the operating
point for the two DC inputs is adjusted separately. In cases
of 2-MPPT operation, two cables are connected per DC input
(DC1 and DC2), one each for DC+ and DC–.
DC cabling for 2 MPPT operation when using aluminum cables
with Al-Cu compression joints
As an alternative, the M88H_121 (ST) can be operated with
only 1 MPP tracker. If this is the case, then the DC connection
proceeds with only 2 cables (1 cable each for DC+ and DC–).
Phoenix Contact jumper for operation with 1 MPP tracker
In addition,
2 jumpers
from Phoenix-Contact are required
(Phoenix order number EB 2-31/UKH - 0201388 for UKH 150).
The jumpers are
not
included in the scope of delivery and must
be ordered separately from commercial outlets
39
Quick installation guide for solar inverter M88H RPI883M121300 RPI883M122300 EU V1 EN 5017414200_00 2019-11-07
Connecting to the solar modules (DC)
M88H_121 (ST) – 1-/2-MPP Tracker operation