Yes, I already do something similarly.
chDecPoint = Mid(CStr(8.1), 2, 1)
strVal1 = Replace(CStr(rVal1), chDecPoint, ".")
strVal2 = Replace(CStr(rVal2), chDecPoint, ".")
etc.
However, I need to know if the decimal character is ALWAYS "." in SQL.
Otherwise I may screw things up at another...
Hi.
Please bear with me, as I am a complete SQL noob.
Problem is this:
I have some VBScript code that writes values to SQL tables.
The code works OK, but I found out that for REAL values, the decimal character on the PC must be set to ".". If regional settings are set to german or danish for...
Coating in stead of having the cup made completely out of teflon sounds like an interesting alternative.
I could have the cup machined in the "normal" way and then have it coated.
Because of the measurement samples conductive and capacitive properties of the material in the cup, I dont want the...
Hi,
I am an electrical engineer with an idea for a new type of sensor. For this I need to have a specially designed cup with smooth rounded surfaces that are electrically isolating and as non-sticking as possible. Teflon (PTFE) comes to mind.
I would like to avoid to have to machine a block of...
Dont remember where to find it in STEP5 (it is 10 years since I worked with it regularly).
But try to locate the USTACK and BSTACK. These will tell you why and where the program stopped.
You may have to look into the manual to get further help on the USTACK and BSTACK.
1. Some option packages on the panels require their own authorisation (SmartService and others).
2. Dont know why the unlimited doesn´t transfer. Can you move it back ?
By the way, you can only transfer the 14 day license ONCE. Once you have done it, it is spent !
3. The transfer of...
Yes, WIN CC Flexible can be used to create small SCADA applications that runs on PCs.
It has the be the "advanced" version (not "standard"). Also, you need a runtime license for each PC that must run the application.
I assume that you use MPI between 314, TP170 and your PC.
There is "Prodave", which is a software library from Siemens.
And there is "OPC" which is an open standard for setting up communication for many different protocols. Siemens has an "OPC server" for MPI, and so has "KepWare", "Merz" and...
To Fritz Frederix:
Hi Rudi,
I liked the "genies" and "super genies" in Citect.
Have you seen anything like that (in terms of reusable objects) in one of the other packages ?
Just wondered if you had any experiance with this particular subject.
Certainly.
You must sit down and specify exactly how you want the starting sequence to work - including safety procedures, and what it must do in an emergency.
When that done you can find out which PLC+HMI to use, and do the programming.
Siemens have OPC servers for Ethernet. It is called "Softnet S7 Ethernet". But you may find that Siemens is difficult to setup. I find that it is not a good selection for a beginner.
I hear that Kepwares OPC servers are a lot easier to setup.
They are double the price, but it would be worth it.
Your requirement that it must be a single-unit PLC certainly narrows down the field of possible candidates.
The Siemens S7-314C-2DP (or S7-314C-2PtP) seems to meet your specifications.
It has 4 hi speed counter inputs. I believe they can be setup to 2 quadrature inputs (but do check it...
Go to Siemens technical forum and ask about the cable details there. There were a few S5-110 posts before. With a little luck there is someone with the cable that he can open up and get the wire/pin definitions...
I think that the S5-110U was programmed with a hardware programming unit, not with a PC (or PG as Siemens has it).
All the code was in a continous block (no subroutines).
Before you do ANY changes to the system, consider how much time and expense it will take to rip it out and replace it with a...
20 discrete signals and 5 analogs ...
Hmmm, I know that it is yesterdays technique, but pulling a number of discrete + analog signals between the two can be the easiest and cheapest way to do it.
Off course, its not so flexible, but if you arrange for a number of spare signals then it cant go...
A safety relay is only required if personal safety is at risk.
As you are protecting machinery rather than people with the vibration switch you do not need a safety relay.
It is possible that you need a safety relay and have to worry about bringing the discs to stop quickly in order to provide...
rugged,
I think that in your case, the E-stop is essentially there to have a handy save-the-pump button, rather than a person-safety stop button.
A pump "normally" doesnt have any dangerous aspects (unless extreme high pressures are created, or the pump is used to drive hydraulic actuators...
Re 1. A contactor in front of the VFD:
Here's some more AB PowerFlex manual text.
"!ATTENTION: A contactor or other device that routinely
disconnects and reapplies the AC line to the drive to start and stop the motor can cause drive hardware damage. The drive is designed to use control input...
