MASS-VIEW® instruments have digital communication possibilities.
Using:
For an example of method 2 see the system overview below.
In this situation, two seperate power networks are shown isolated by the
RJ-45 Power Isolator, only the two datalines are connected between the two networks.
On the PC side, please make sure the correct
device driver is installed. This device driver will install an additional (virtual) COM-port on the PC.
The last step is to install the software which acts as the master on the RS-485 bus. We do not deliver Modbus software but we advise to use the software which is developed by Huisman.IT. The software that works with MASS-VIEW
® is called
Go2Measure .
This is an example how to connect 5 MASS-VIEWs to one Plug-in Power Supply (PiPS-MV) using an Y-adapter cable RJ-45 (7.03.241), 5 RS-485 cables for MASS-VIEW (7.03.467) and a RJ-45 multiport connector(7.03.299). This example is only valid as a power supply solution, not for a RS-485 digital network because the terminal set (7.09.214) is missing.
All MASS-VIEW models which have O2 as a pre-installed gas are degreased.
The MASS-VIEW flow meters can measure humid air.
Humid air can be seen as a mixture of water and air. The physical properties of the mixture will differ from those of dry air. Therefore, the inaccuracy of a thermal mass flow meter calibrated for dry air could increase when humid air is applied instead of dry air.
What we have seen is that as long as there is no condensation the inaccuracy caused by humidity is less than 0.1% FS for models MV-104, MV-106, MV-304 and MV-306 and 0.3%FS for models MV-102 and MV-302.
MASS-VIEW can be connected to a computer and is able to communicate over RS-232.
Herewith an overview of the right cabling.
- If you bought the interconnecting cable with loose end then you should arrange a DB-9 connector and mount the wires according to the hook-up diagram which is available in the brochure, manual or on the product information page in the shop.
- There is also a possibility to order a special RJ-45 male cable to DB9 female which should be connected to a Split-cable (Y) in order to use both power supply and RS-232, see the picture below. If there is no RS-232 DB9 male connector available on your computer, order the RS-232 to USB 2.0 convertor and use the USB port.
It is currently not possible to set the counter units in the MASS-VIEW to use "mass" units (ug, mg, g, kg) using the menu. There is a "work around" by setting this parameter using a Windows PC with RS-232 or USB.
This is the procedure how to do this.
Your Question:
Customer can not read the Counter unit in mass flow
Solution:
Change the sensortype of the instrument using FlowDDE ( parameter 22 from 131 into 130).
Action to take:
--change parameter 22 from value 131 to value 130:--
Connect instrument to a Serial Comm port of a PC.
-Install
FlowDDE Software
-Make FlowDDE connection with the instrument and write/read values by FlowDDE server menu "Test FLOW-BUS and DDE F6 ".
Select the parameter number by the dropdown menu or by entering the number in the box, select read or write as described.
--change parameter 22 from value 131 to value 130:--
-Parameter 7 (initreset) -->Write value 64 (Soft will enable writing parameter 22).
-Parameter 7 (initreset) --> Read parameter and check value.
-Parameter 22 (Sensortype)-->Write value 130.
-Parameter 22 (Sensortype)-->Read parameter and check value.
-Parameter 7 (initreset) -->Write value 82 (NormalRunningMode).
-Parameter 7 (initreset) --> Read parameter and check value.
Now the Counter value is available in the mass units
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The MASS-VIEW® operates on the principle of direct thermal mass flow measurement. The thru-flow design sensor consists of a heater resistor and a temperature sensing resistor. Both resistors are made of temperature sensitive resistive material that is covered with a stainless steel tube. The necessary heating power to keep the temperature difference between the heater resistor and the sensing resistor at a constant level depends on the mass flow. A different and unique heater current is produced for each value of the flow. The measurement principle described is called Constant Temperature Anemometry (CTA).
The transfer function between mass flow and output signal can be described by the equation: 
Vsignal = output signal
K = constant factor
(includes λ – heat conductivity, Cp – specific heat, μ – dynamic viscosity and ρ – density of the gas)
Φm = mass flow
Based on this concept, mass flow can be measured with low pressure drop, mainly caused by the gas fittings. Compared to traditional thermal MFMs and MFCs with by-pass, the direct measuring MASS-VIEW® is less sensitive to humidity and contamination.
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MASS-VIEW® has two communication options:
- FLOWBUS over RS-232
- MODBus RTU or ASCII over RS-485
there is no FLOWBUS over RS-485 communication possible.
FLOWBUS over RS-232 is mostly used to communicate directly to a PC (running FLOWDDE + FLOWPLOT). RS-232 is a point-to-point connection.
MODBus RTU or ASCII is mostly used when a fieldbus is used to connect several instruments to one bus.
The MASS-VIEW® flow meter has two alarms connected to a relay/switch. This relay is already included in the MASS-VIEW®. One side of the switch is connected to ground (pin 4, 0 Vdc) and the other side is connected to Pin 3 (alarm high). The other relay is also with one side connected to ground (pin4, 0 Vdc) and the other side is connected to Pin 5 (alarm low). Please read the manual for more information about the alarm settings you can program.
Switching current 0.5 A, 24 Vdc
We have made a maximum capacity list for all MASS-VIEW® models in different flow units
To determine the pressure drop over a MASS-VIEW instrument, you should visit our pressure drop section where we have published all information per gas per MASS-VIEW instrument at different flows and different inlet pressures.
This video shows what happens when a MASS-VIEW® mass flow meter is powered on the first time. (video length 43 seconds)
After MASS-VIEW is powered up:
- first the pre-installed fluid can be chosen
- then the corresponding range
- the digital output /communication bus
(analogue output (0-5V) is always on)
- and at last, the security settings can be changed
Your instrument is ready for operation.
The following counter units are available for MASS-VIEW(r):
- when mass flow units are selected in the measure->type menu: μg; mg; g and kg
- when volume flow units are selected in the measure->type menu: ln; mm3n; mln; cm3n; μln; dm3n; m3n; μls; mm3s; mls; cm3s; ls; dm3s; m3s
The following flow units can be selected on a MASS-VIEW(r):
- mass flow units: μg/h; μg/min; μg/sec; mg/h; mg/min; mg/s; g/h; g/min; g/s; kg/h; kg/min; kg/s
- volume flow units (at normal conditions): μln/h; μln/min; μln/s; mln/h; mln/min; mln/s; ln/h; ln/min; ln/s; ccn/h; ccn/min; ccn/s; mm3n/h; mm3n/min; mm3n/s; cm3n/h; cm3n/min; cm3n/s; m3n/h; m3n/min; m3n/s; scfh; scfm; scfs; sccm; slm
- volume flow units (at standard conditions): μls/h; μls/min; μls/s; mls/h; mls/min; mls/s; ls/h; ls/min; ls/s; ccs/h; ccs/min; ccs/s; mm3s/h; mm3s/min; mm3s/s; cm3s/h; cm3s/min; cm3s/s; m3s/h; m3s/min; m3s/s
every few seconds, the MASS-VIEW® writes the countervalue to a non-volatile memory to be sure no data is lost after a powerfailure
The counter function will start counting a measured value when the instrument measures a value of 2% or higher of its capacity. Below 2% nothing is counted.
We have a (backdoor) solution for this, you can always use abc as password and then change the password again.
