Magtrol MVD100 User Manual

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MAGTROL

1. INTRODUCTION

The MVD 100 measuring Amplifier is designed to control forces, loads, pressures, etc. in connection
with analog sensors, predominantly with DMA transmitters. After conditioning the actual value
signal, the device is digitally assisted by a processor (MSP 430/TI). A total of 3 switching thresholds,
which include hysteresis, switching performance, and pick-up delay, can be programmed and
generated.

2. DESCRIPTION

Low drift precision operational amplifiers are used to amplify the sensor voltage to a level which can
be processed by the processor’s own A/D converter. The digitalized actual value is then compared
with several set values. Switching signals are triggered if the actual value coincides with, or exceeds
any of these set values. The relevant set values are entered via a keyboard with LCD display which
can be plugged into the amplifier’s PCB. This control unit may remain connected or be removed
from the amplifier after programming since it does not affect the amplifier’s function.

Digital measuring Amplifier

Type MVD100

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MVD100

User’s manual

3. INPUT MODE

3.1 input keys

The control unit is equipped with 1 switch and 3 keys which provide the following functions :

C1 switch To switch from measuring mode to programming mode

K1 key To advance parameter display

K2 key Input of numerical values (set value, hysteresis, delay time)

K3 key Transmission of input data to memory

Display

measuring

programming

C1

K1 K2 K3

Figure 3.1 control unit

3.2 Display

An 8-digit one-line LCD display serves as the input control display. The display is active both in
measuring and programing mode. The percentage load of the sensor is shown in the measuring mode.

3.3 input proceDure

1. Set the C1 switch to position 2 (programming mode). The following image will appear in the
display: S1 xxx %

This means in normal language:
The set value of the first threshold (S1) amounts to XXX % at present. The cursor is at the
lowest-order position, flashing.

2. Now the K2 key may be pressed in order to gradually increase the value displayed by +1 with
every keystroke. The cursor jumps to the left by one digit position if the K2 key is depressed for
two seconds or longer. Again press the K2 key in order to set the left digit to the desired value.
Depress the K2 key for two seconds to return the cursor to the starting point.

3. Press the K3 key in order to transmit the numerical value entered to the parameter memory
(EEPROM) where it will be stored in the event of a power failure.

4. The K1 key may be used in order to scroll to any parameter field.

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MVD 100

User’s manual

3.4 parameter list

Clocking sequence when pressing K3:

S1 Limit value 1 / set value (xxx %)

H1 Hysteresis for limit value 1 (xxx %)

T1 Pick-up delay of limit value 1 (xx.x sec)

I1 Switching point, normal (0) or inverse (1)

S2 Limit value 2 / set value (xxx %)

H2 Hysteresis for limit value 2 (xxx %)

T2 Pick-up delay of limit value 1 (xx.x sec)

I2 Switching point, normal (0) or inverse (1)

S3 Limit value 3 / set value (xxx %)

H3 Hysteresis for limit value 3 (xxx %)

T3 Pick-up delay of limit value 3 (xx.x sec)

I3 Switching point, normal (0) or inverse (1)

A Adjusted zero point value

E Adjusted end point value

Special feature:

If 000% is entered for S1 and/or S2 and/or S3, pressing the K3 transmission key will not result in
the 000 value being transmitted to the memory, but instead the actual value put in from outside will
be transmitted which has been converted by the AD converter. This is a self-learning function which
can perform parameterisation directly with the maximum load applied.

3.4 start/enD aDjustment

1. Press K1 in order to select parameter A (start adjustment).

2. Unload the sensor (scales).

3. Press the K3 transmission key.

4. Press K1 in order to select parameter E.

5. Apply a known force (weight) to the sensor.

6. Press the K3 transmission key.

Attention: the vAlue 100% is AutomAticAlly Assigned to the weight now

stored.