The amplifier module is snapped onto top hat rails according to EN 60715. The electrical connection is established via screw terminals. The module is operated with 24 V direct voltage. A power supply unit [1] supplies all internally required positive and negative supply voltages. As soon as the power supply unit is in operation, the green LED (“power”) lights up.
When a command value voltage is applied at the differential input and a positive enable voltage at one of the enable inputs, one of the two solenoids (“a” or “b”) at the valve is controlled. The solenoid current depends on the command value level (see output characteristic curves) and on the position of the selector switch [13] for the valve type. Which one of these two solenoids is controlled depends on the polarity of the command value and on the activation of the enable inputs (see functional table).
The solenoid current (actual value) is measured and compared to the externally provided command value. Any occurring differences, caused e. g. by temperature changes of the solenoid or changes to the supply voltage are compensated. Using potentiometers “Gw1” and “Gw2”, the maximum current of the solenoids and thus the maximum valve opening can be set. Which one of the potentiometers is activated by the enable inputs, is indicated by an illuminated yellow LED. Using potentiometer “S” (step level), tolerances in the valve overlap can be compensated. It is to be ensured, however, that the rated current of the solenoids is not exceeded.
The amplifier module is equipped with a ramp generator [3]. Using the corresponding potentiometer “t”, rise and fall times of the solenoid current can be set.
By a changeover switch at the front side of the module, the default setting of the valve type to be controlled can be selected.
Functional table of the enable inputs and the solenoid control
Enable inputs | Command value voltage Ucommand |
active solenoid | active LED | Mode | |
Enable 1, UF1 active | Enable 2, UF2 active | ||||
Yes | No | > 0 V < 0 V |
b a |
H1 | 1 |
No | Yes | > 0 V < 0 V |
a b |
H2 | 2 |
Yes | Yes | > 0 V < 0 V |
a b |
H2 | 2 |
No | No | > 0 V < 0 V |
‒ ‒ |
‒ | ‒ |
- Component series 1X
- Analog, Modular design
- For valves:
4WRA 6…1X,.WRZ…7X and 3DREP 6…2X
4WRA 10…1X
.WRZ..5X, .WRZ..6X and 3DREP 6…1X