VDH ALFA 75-MTT User Manual

User manual
ALFA 75-MTT
MilkTankThermostat.
VDH doc. 080723
Software: ALFA75-MTT

* Description.

The ALFA 75-MTT is a Milk tank thermostat with the next functions:
- Cooling:
- Stir:
- Temperature alarm: An alarm will be given when the adjusted minimum and maximum temperature values
- Cooling time alarm:
- Digital input:

* Installation.

On the connection diagram from the ALFA 75-MTT is shown how the sensor, supply and relays should be
connected. After power up a self test is started. If the self test is completed the display will show the measured
temperature.

* Control.

The ALFA 75-MTT can be controlled by four push buttons on the front:
(SET)
(UP)
(DOWN) - lower the adjusted value.
(STIR)

* Normal operation.

During normal operation will the temperature from the temperature sensor be shown. Range 0,0 till 80,0  C.

* Viewing the set point.

By pushing the SET key the set point appears in the display. The
A few seconds after releasing the SET key the set point disappears and the measured temperature
is shown again.

* Changing the set point.

Push the SET key and the set point appears on the display. Release the SET key. Push the SET key again
together with the UP or DOWN keys to change the set point. A few seconds after releasing the SET key the set
point disappears and the measured temperature is shown again.

* Adjusting internal parameter.

Next to the adjustment of the set point, some internal settings can be made like differentials, sensor offset and
stir functions.
By pushing the DOWN key for more than 10 seconds, you enter the 'internal programming menu'.
On the left display the upper and the lower segments are flashing. Over the UP and DOWN keys the required
parameter can be selected (see table for the parameters).
If the required parameter is selected, the value can be read-out by pushing the SET key. Pushing the UP and
DOWN keys allows you to change the value of this parameter.
If no key is pushed for 20 seconds, the ALFA 75-MTT changes to it's normal operation mode.
File: Do080723.WPD
On adjusted set point (f.i. 4,0  C).
Continuos during cooling and on adjustable intervals when cooling is off.
Manuel stir after pushing the button on the front (with time limitation)
are exceed. The alarms are reported with an error code on the display, the buzzer will
be activated and the relay will be energized. A time delay can be adjusted for the alarms.
When the temperature doesn't reach the temperature set point within the adjusted time,
an alarm will be given (with buzzer and relay).
If the digital input is closed during cleaning than the control will stop and the display will
only show the cleaning temperature.
- viewing / changing from the adjusted value and alarm reset.
- raise the adjusted value.
- Start stir manual.
Version: v1.0
1
Date: 27-05-2008
Range: 0,0/+80,0  C pro 0,1  C
led starts flashing to indicate this.