Vermes MDS 358X user Manual.pdf - 第50页
Micro disp en sing Va lve VTK - TR -BA- 072e - 1 - User Manua l MDS 358X S eries 39 5 Microdispensing Valve This chapter c ontain s relevant inf ormation a bout th e valve. I t descr ibes the struct ure and th e hardw ar…
Control Unit MDC
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VTK-TR-BA-072e-1 - User Manual MDS 358X Series
4.6 Memories of the MDC
The MDC contains several memories to save parameter setups.
The first one is the RAM (Random Access Memory). Here the parameters of the current dispense
process will be saved. This memory will be erased when the controller is switched of or
disconnected from power. When starting again, the MDC will load the first of eleven parameter
memory sets saved on the EEPROM (Electrically Erasable Programmable Read Only Memory) into
the RAM. This first parameter setup is also called the “EEPROM current working parameter
configuration”, or short “working configuration” or “EEPROM working configuration”.
The parameter set in the EEPROM working configuration is usually the same as the parameter set
saved in the RAM memory. When using the keypad to program the controller, the two memories
will always have the same contents. The only way to create a difference in the parameter set
saved in the RAM and in the EEPROM working configuration is by using some special commands
through the RS-232C.
The remaining ten EEPROM memory sets can be used to save different parameter setups when
programming the controller through the keypad interface (use the command [save]).
In order to change the values saved in the EEPROM working configuration you may use the MDC
keypad (enter the parameters in the menu “Pulse Parameters”, then press [enter]).
Or you may use one of the following commands via RS-232C:
• TRIGGER:ASET:<Rising>,<Open Time>,<Falling>,<Needle Lift>,<Number of Pulses>,<Delay>,1
• STRIGGER:ASET:<Rising>,<Open Time>,<Falling>,<Needle Lift>,<Number of Pulses>,<Delay>,1
All values transmitted to the control unit by one of the following commands will not be saved in
the EEPROM working configuration.
• TRIGGER:ASET:<Rising>,<Open Time>,<Falling>,<Needle Lift>,<Number of Pulses>,<Delay>
• STRIGGER:ASET:<Rising>,<Open Time>,<Falling>,<Needle Lift>,<Number of Pulses>,<Delay>
Instead it will remain in the RAM memory until erased by another RS-232C command, or when
the control unit is switched OFF and the EEPROM is read out into the RAM during restart. The
reason for having these two different types of commands (the distinction is the “1” at the end) is
that it takes up to 1 sec to save the parameter set in the EEPROM.
On top of the working configuration and the ten parameter setups there is another parameter
set-ting saved in the software on the EEPROM. This is called the “factory setting”. It cannot be
changed by the user. It may be loaded to the working configuration and the RAM memory after
major disturbances of the system.
Additionally there is the possibility to save combinations of setups, so called “Scenarios” (see
paragraph 7.9 "Scenarios", page 70).
Microdispensing Valve
VTK-TR-BA-072e-1 - User Manual MDS 358X Series
39
5 Microdispensing Valve
This chapter contains relevant information about the valve. It describes the structure and the
hardware configuration.
5.1 Composition
The Microdispensing valves of Vermes Microdispensing are modular. A valve is composed of
seven different modules:
• Valve body (includes Electronics module and Actuator system) (1)
• Tappet (not visible) (2)
• Tappet sealing (not visible) (3)
• Nozzle insert (not visible) (4)
• Nozzle fixation nut (5)
• Heater MDH-48-BY with fluid box (6)
• Media supply (7)
Fig. 18: Composition
Microdispensing Valve
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VTK-TR-BA-072e-1 - User Manual MDS 358X Series
The valve body (1) accommodates the electronics module, the actuator system, the adjust screw
and the tappet (not visible in the picture). The electronics module holds the electronics to receive
the actuator and sensor signals. Here are the connectors for sensor cable and actuator cable
integrated in the surface of the case; they have to be linked to the control unit. The electronics
module is connected to the actuator system, representing the core of the microdispensing valve.
The actuator system houses the sensor, the piezoelectric element and the mechanics to drive the
tappet. Actuator case and mechanics are sealed for protection against dust and contamination.
The adjust screw (8) is at the top end of the valve body.
At the bottom of the valve is the inlet where the tappet (2) runs. The tappet can be exchanged.
Powered by the actuator the tappet moves with high speed back and forth. It hits the dispensing
medium and presses it through the opening of the nozzle insert. Tappets can be made of
ceramics, of carbide metal or of poly diamond. They can have different forms or sizes. A tappet
should be checked and cleaned regularly or exchanged if necessary (see paragraph 10.2.1
"Maintenance of the Tappet", page 138).
The connection between valve body and fluid box is made up of the tappet sealing (3). There are
different types of tappet sealings, e.g. the Tappet Sealings PE and Tappet Sealings PTFE, which
have to be used together with a tappet centering piece.
A small but important module is the nozzle insert (4), which has to be considered as a wearing
part. Thanks to the bayonet fluid box, it can easily be cleaned and exchanged in case of need.
VERMES Microdispensing offers a large selection of different nozzle inserts to allow for optimum
dispensing results, according to the current application. They can differ in form and material.
The nozzle fixation nut (5) contains the nozzle insert (NI).
The fluid box (6) is integrated into the heater MDH-48-BY. It is thermally isolated from the
actuator system. Its purpose is to transport the liquid from the cartridge or the tank to the nozzle
fixation nut. In order to simplify independent cleaning, this module can easily be disengaged
from the valve, just by one click, thanks to the bayonet system. Information how to assemble a
fluid box you can find in paragraph 6.2, page 45. In case you need no heating for your
application, you can use the Mounting Body BY (order no. 1014369) instead of the heater MDH-
48-BY.
The media supply (7) supplies the dispensing medium and is connected with the fluid box.
VERMES Microdispensing GmbH has many different configurations available (see Page 158). For
smaller amounts to be dispensed you can use a cartridge. They come in different sizes and types.
For larger amounts, you can use a tube connector to connect a pressure tank with the fluid box.