Xylem Lowara ResiBoost MMW Series, Installation, Operation And Maintenance Manual, Page: 40 / 244

• For the models MMW and MTW, the sensor is in-
ternal. Contact the assistance service.
• For the models MMA and MTA, the sensor is ex-
ternal and the alarm is triggered with a < 3.2 mA
or > 22 mA signal.
• Check that the sensor and connector are con-
nected.
• Open the cover and check that the power cord of
the sensor is connected and secured to the ter-
minals. See Figure 15 .
• Check the cable of the sensor is connected cor-
rectly. See Figure 15 .
• The power cable of the sensor has deteriorated:
replace the cable.
• Replace the faulty sensor.
N° Text on
the dis-
play (*)
Model Descrip-
tion
Reset
A6 OVER
TEMP
MMW
MTW
MMA
MTA Alarm in-
dicating
that the
power
module
of the
converter
has su-
perheat-
ed
Automat-
ic.
Troubleshooting:
• Models MMW and MTW: the temperature of the
power module has reached the value of 80°C. In
AUTOMATIC mode, the converter stops the
pump and does not restart it until the tempera-
ture falls below 60°C.
• Models MMA and MTA: The cooling fan turns on
at 60°C and turns off at 50°C (both MMA12 and
MTA10 have a fan). If the temperature reaches
85°C, the output frequency of the motor is auto-
matically reduced by 3Hz down to 75°C. At 95°C,
and in AUTOMATIC mode, the converter stops
the pump and does not restart it until the temper-
ature falls below 80°C.
• Models MMW and MTW:
• The temperature of the water exceeds the
limits for use of the converter. See Technical
data .
• The power module is faulty: contact the assis-
tance service.
• The ambient temperature exceeds the limits for
use of the converter. See Technical data .
• Models MMA12 and MTA10:
• The cooling fan is faulty. Contact the assis-
tance service.
• The cooling fan does not work.
• Open the cover and check the power cable of
the fan is connected and secured to the rela-
tive terminals. See Figure 15 .
N° Text on
the dis-
play (*)
Model Descrip-
tion
Reset
A7 SHORT
CIRC
MMW
MTW
MMA Alarm in-
dicating
a short
Automat-
ic. A max
of 4 at-
N° Text on
the dis-
play (*)
Model Descrip-
tion
Reset
MTA circuit on
the pow-
er supply
side of
the mo-
tor
tempts to
start are
made at
2 second
intervals.
The
pump is
perma-
nently
locked if
the alarm
perse-
veres af-
ter the
reset
tests.
An automatic function of the converter that detects
current consumption while the motor is running. The
converter cuts out the power supply to the motor and
remains locked.
Troubleshooting:
• The motor is damaged and must be replaced.
• The power cable of the motor is faulty or worn:
replace the cable.
N° Text on
the dis-
play (*)
Model Descrip-
tion
Reset
A8 OVER
VOLT
MMW
MTW
MMA
MTA Alarm in-
dicating
the volt-
age sup-
ply of the
converter
is high
Automat-
ic
An automatic function of the converter that detects
the voltage value of the power line. The converter
stops the electric pump when the voltage value ex-
ceeds the permitted limit (254 V). The pump auto-
matically starts up when the voltage drops below the
limit (chapter 2.5).
Troubleshooting:
• Problems with the power line: contact the utility
provider.
• For systems with more than one pump, the elec-
tric pump with converter acts as a current gener-
ator when the non-return valve of the hydraulic
system is faulty. The water flows through the
non-return valve in the opposite direction.
• The DC Bus power circuit of the converter is faul-
ty.
N° Text on
the dis-
play (*)
Model Descrip-
tion
Reset
A9 UNDER
VOLT
MMW
MTW
MMA
MTA Alarm in-
dicating
that the
voltage
supply of
Automat-
ic
en - Original instructions
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