User manual

µC

SE process chiller +030220416 - rel. 2.2 - 25.01.2013

4.3 Minimum and maximum fan speed

calculation

This procedure should only be performed when the fan speed control boards are

used (code MCHRTF*). When ON/OFF modules are used (code CONVONOFF0) or

alternatively the PWM to 0 to 10 V converters (code CONV0/10A0) are used,

parameter F03 should be set to zero, and parameter F04 to the maximum value.

Given the different types of motors existing on the market, it must be possible to

set the voltages supplied by the circuit board corresponding to the temperatures of

minimum and maximum speeds. In this regard (and if the default values are not

suitable), proceed as follows:

• set the parameter F02=0 and reset F03 and F04 to zero;

• the condensation set point has been modified to take the output signal to the

maximum value (PWM);

• increase F04 until the fan operates at a sufficient speed (make sure that, after

having stopped it, it can rotate freely when released);

• “copy” this value to parameter F03; this sets the voltage for the minimum speed;

• connect a voltmeter (set to AC, 250V) between the two “L” terminals (the two

external contacts);

• increase F04 until the voltage stabilises at around 2 Vac (inductive motors) or 1.6,

1.7 Vac (capacitive motors);

Once the value has been found, it will be evident that even when increasing F04

the voltage no longer decreases. Do not increase F04 further so as to avoid

damaging the motor;

• restore the correct condensation set point.

The operation is now completed.