Western Co WRM20 Manuel De L'utilisateur page 13

PV CHARGE CONTROLLER
WRM20
WRM20+
with RS-485 port WBus protocol
WRM20 is a complete solution for off-grid PV systems to supply power to road
signs systems, lighting systems, small low voltage systems and for the recharge
of batteries inside caravans. This model of charge regulator has a circuit for the
research of the maximum PV module power (MPPT): regardless of battery
voltage and its charge status, WRM20 works with PV module in its maximum
power point maximizing the energy that comes from the module and then
loaded into the battery. Unlike PWM charge regulators that require PV
modules with 36 cells for the recharge of batteries at 12V and PV modules with
72 cells for the recharge of batteries at 24V, thanks to WRM20 controller this
project restraint is no more necessary. With MPPT controllers you can install
the cheapest PV modules used in grid connected systems with a number of
cells different from 36 or 72. In addition you can use amorphous PV modules
that normally are not suitable for PWM charge regulators.
Several programs of load management, selectable by the user, make WRM20
the complete solution in many applications i.e. to supply power to TVCC
cameras that have to work only during the day, or for blinking light systems /
road signs that have to work only during the night, or to supply power to
lighting systems that have to work only for a certain number of hours during
the night. WRM20 detects the day/night status according to the PV module
voltage; therefore, it's not necessary to connect further sensors to the
regulator. A wide display shows battery voltage, PV module charging current,
output load current and other variables.
WRM20+ model is provided with a RS-485 communication port that
implement WBus protocol and allows to connect WRD display by Western CO.
for datalogger and remote control. Western CO. provides this communication
protocol on this port so the user can implement his own device datalogger or
remote control.
WRM20 and WRM20+
User manual
1
EN
Step down MPPT charge
Maximum PV module power
− 310 W for 12 V battery
− 620 W for 24 V battery
Integrated blocking diode
For sealed / GEL, flooded lead
acid batteries, lithium-ion or
LiFePO4 batterie batteries
Temperature-compensated
12V / 24V battery auto-detect
voltage
18 programs for load
management
LCD display user interface
Protections:
− Load-disconnect in case of low
battery
− Over-temperature
− Battery polarity inversion
− Output overload protection
IP20 metal box
RS-485 communication port with
WBus protocol owned by Western
CO. for data-logger or remote
control with display WRD
(only for WRM20+ version)
REV 1.6 17-02-2020