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5.4.3 BELT
IMPORTANT!
The belt function is critical in the automatic operation of the mixer. The belt is the first function in the series
hydraulic circuit, which feeds all the downstream functions such as the cement auger, fly ash and color. All the
downstream functions including the water and the admix use the belt speed as the primary variable in the
calculation of each functions set point values. If the belt speed sensor is not providing feedback (ie. 0 RPM) then
all the other functions set point equations will multiply by zero resulting in a zero setpoint. It is possible to
continue to run the mixer in a limp mode. This only applies to mixes without fly ash (AUX1) or color and if the
cement ratio in the mix design is set at or near 100%. To activate the limp mode the operator can select Cement
Full, Water Manual, Belt Manual and Admix Manual. There will be no belt counts in this limp mode (ie. no
volume totals), but the operator can still run the mixer manually this way if need be.
If the Commander system is showing an auto belt alarm,
then this is an indication that the output speed is not
matching the set-point speed.
Check to see if the actual RPM is showing in Digital
Readouts and that it matches the set-point RPM when
mixing (see the CANBUS Speed Sensor section for more
detailed troubleshooting). Also, confirm that the engine
high idle speed is working properly. If there is not enough
flow from the belt pump, then the belt will not meet it’s
setpoint.
If the oil temperature is not above 15°C (60°F) and the belt
is set for maximum speed then slow the belt speed down to
50% or warm up the system by running the mix auger
empty for 5 min to get the oil temperature up to at least
30°C (90°F) before trying to run the belt at full speed. Very
cold oil is too high a viscosity to allow for max oil flow
through valves without a warmup first.
In the Electrical Diagnostics screen select the belt current
diagnostic and check and see if the current increases when
the belt is activated. Also, confirm that the belt speed
solenoid indicator light is on.
If the speed sensor is working properly and electrical
current is going to the belt valve coil the next step is to
check the belt pressure in the Diagnostics screen. Run the
belt in belt unload mode and watch the belt pressure. If the
pressure is under 2000psi and the belt is turning, then the
belt itself is free. If the pressure is at the pump’s
compensator setting of about 3600psi then something may
be jamming the belt.
If the belt is turning freely in belt unload, but the pressure is
at or near 3600psi when running all downstream functions
A
B
C
Summary of Contents for P Series
Page 1: ...1 PROALL Mobile Mixer Service Manual P Model MX04703 August 2020 Rev 1 0 ...
Page 20: ...20 has been removed and not replaced then the charge pressure will drop to zero C ...
Page 85: ...International Manufacturing Inc P P1 OUT IN OUT IN 2 1 3 IN S1 S2 2 1 3 OUT IN ...
Page 100: ... ADMIX 1 ADMIX 2 WORK LIGHTS ...
Page 101: ... COOLER 1 VIB1 SPARE VIB1A SPARE VIB2A VIB2 VIB3 VIB4 VIB5 ...
Page 105: ... BATTERY V BATTERY V ...