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The threads that wouldn't die...
- PC reliability?
- Windows, real time
- PID loops
- PCs vs. PLCs
- Replacing people
- MS 'monopoly'?
- Software quality
- Where do we go from here?
- Why pay?
- PC reliability?
- Windows, real time
- PID loops
- PCs vs. PLCs
- Replacing people
- MS 'monopoly'?
- Software quality
- Where do we go from here?
- Why pay?
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Posts from...
Tuesday, September 23, 2008
Neutral CT for Transformer REF protection.
What exception code does the unit transmit if the master attempts to write a read only register?
New Replies:
By Mark on 23 September, 2008 - 11:14 pm -
By Mark on 23 September, 2008 - 11:14 pm -
Hello,
Differing allowed. I knew when I posted the reply someone would come up and say but but...
By Michael Griffin on 23 September, 2008 - 8:29 pm - Read-only registers are called "Input Registers". Read-write registers are called...
By Issac on 23 September, 2008 - 8:01 pm - I beg to differ. The Modbus standard does define read/write for the 4 basic data registers in...
By Fred Loveless on 23 September, 2008 - 7:54 pm - Acutally Input registers 0x04 and input coils (discrete inputs) 0x02 are essentialy read only. You...
By Mark on 23 September, 2008 - 11:09 am - Hello,
AFIK, MODBUS does not define any registers as "read only".
Having said that, I...
Maximum length of RS 485 cable between 2 devices
New Replies:
By Michael Griffin on 23 September, 2008 - 8:31 pm -
By Michael Griffin on 23 September, 2008 - 8:31 pm -
In reply to Arun Joshi of Sunlux Technologies: I'm sure you have plenty of nice products you would...
By Arun on 23 September, 2008 - 2:03 am - Dear Sir,
To give you a brief background of Sunlux, we are an Industrial Embedded IT Company...
Can we use a DP transmitter to measure the water level in a vacuum tank? If not, what is the solution for it?
New Replies:
By Dick Caro on 23 September, 2008 - 8:26 pm -
By Dick Caro on 23 September, 2008 - 8:26 pm -
Certainly! Just connect the vacuum area to the low pressure side of the DP transmitter, and the...
By Roy Matson on 23 September, 2008 - 10:05 am - Do you have the LP connection connected to the top of the tank? The differential should not drop...
Why speed and accel/decel differ?
Comparison
New Replies:
By Subhrendu Malakar on 23 September, 2008 - 8:23 pm -
By Subhrendu Malakar on 23 September, 2008 - 8:23 pm -
You can also look into PAS at http://www.pas.com/ who have an integrated Loop Monitoring &...
By Rodrigo Ivan on 23 September, 2008 - 10:02 am - I suggest TriSolutions,
...
Must I use Relays switched by the PLC and volt free contacts to utilise Drive's own 24v Supply?
New Replies:
By Roy Matson on 23 September, 2008 - 8:21 pm -
By Roy Matson on 23 September, 2008 - 8:21 pm -
You should be OK. Most of the AB 24 VDC Output modules are ground referenced (sourcing). Connect...
By James Ingraham on 23 September, 2008 - 7:39 pm - In theory, you should be able to use a 24VDC PLC output directly to a VLT 2800. However, the 24VDC...
where will I get the complete manual for DeltaV?
New Replies:
By Jim Cahill on 23 September, 2008 - 8:18 pm -
By Jim Cahill on 23 September, 2008 - 8:18 pm -
I saw a recent update to an old thread so I thought I'd point out the DeltaV Books On-line is...
how to calculate the size of the medium voltage cable
New Replies:
By najeeb on 23 September, 2008 - 8:14 pm -
By najeeb on 23 September, 2008 - 8:14 pm -
Dear Phil,
I saw your information on web site, I want to calculate feeder cable and its...
Janette electric actuators?
New Replies:
By Issac on 23 September, 2008 - 8:10 pm -
By Issac on 23 September, 2008 - 8:10 pm -
I am fairly certain that Janette was bought by Leeds & Northrup. If that's the case, L&N...
Can anyone direct me to a web site that reviews and/or compares the VFDs of different manufacturers, with particular interest in the Ethernet communication feature?
New Replies:
By Robert Willis on 23 September, 2008 - 8:02 pm -
By Robert Willis on 23 September, 2008 - 8:02 pm -
In addition to what has been said so far I would also suggest that you take a look at how your...
By Bob Peterson on 23 September, 2008 - 10:13 am - I would also suggest putting a switch near the drive itself. Long Ethernet runs can be...
By Brent on 23 September, 2008 - 1:13 am - There are many options, but we have had success
using AB Powerflex 70s over Ethernet IP. Make...
these two concepts are ambivalent, preventing one in maintaning single opinion about them...
New Replies:
By Steve YATES on 23 September, 2008 - 7:52 pm -
By Steve YATES on 23 September, 2008 - 7:52 pm -
The basic concept of the two techniques is the same, the main difference is that FNICO is limited...
By Bruce Durdle on 23 September, 2008 - 3:03 pm - FISCO equipment follows Intrinsically Safe rules and is therefore of high integrity - it maintains...
By Dick Caro on 23 September, 2008 - 1:53 pm - Here is a quotation taken directly from my book, The Consumer's Guide to
Fieldbus Network...
Does anybody have experience with Ethernet IP Stepper Indexer/Drivers?
New Replies:
By Jack on 23 September, 2008 - 7:51 pm -
By Jack on 23 September, 2008 - 7:51 pm -
Hi Davis,
Thanks for your reply, but I'm afraid my original post may have been
misleading...the...
By William Gentry on 23 September, 2008 - 11:08 am - If they are "resigned" to using AB for closed loop stepper, they don't have to. Our...
I am having problem in synchronization of redundant chassis...
I am having an issue talking to a SEL 2030...
Kindly tell me how generator increase its load by just increasing the fuel of prime mover...
New Replies:
By Bruce Durdle on 23 September, 2008 - 3:06 pm -
By Bruce Durdle on 23 September, 2008 - 3:06 pm -
Hi blackstoneboy,
Power factor depends on the alternator excitation and does not depend on the...
By blackstoneboy on 23 September, 2008 - 9:50 am - Can anyone help me on this...
We have synchronized 6 units of generators but not connected to...
By Bruce Durdle on 23 September, 2008 - 1:25 am - Hi CSA,
I can add a few !!! if you like.
It's all to do with relative motion - if you are...
I am trying to monitor frequency when spike about preset limit
how can I generate 12 volts AC or DC using only household water pressure, and what is the smallest this generator can be? Can it be smaller than 120cc?
New Replies:
By Sean on 23 September, 2008 - 10:26 am -
By Sean on 23 September, 2008 - 10:26 am -
@ Robert
A few things.
First off, there it typically a pressure gradient in the water...
I'm looking for an 'off the shelf' device to control (or at least sense)reverse power flow or power flow direction between 2 AC generators.
Upload application from Panelmate 1000
New Replies:
By Bob Peterson on 23 September, 2008 - 10:12 am -
By Bob Peterson on 23 September, 2008 - 10:12 am -
The PM1000 is the old 5" LCD thing that has been off the market for 10+ years. Its not...
By Trevor Ousey on 23 September, 2008 - 1:18 am - Oops, my mistake. I was having a few ales and misread.
It would nearly be worth purchasing the...
speed of gas turbine raised more than 4 % droop.
New Replies:
By CSA on 23 September, 2008 - 10:10 am -
By CSA on 23 September, 2008 - 10:10 am -
It's really difficult to say for certain without being able to look at the CSP of your unit and we...
how do we know the correct value of current to pe applied(value at which relay picks up)?
If we increase time delay for shutdown to 30 secs, fuel changeover valve would change position & there would be no shut down BUT m/c would run on furnace oil without additive dosing for approx. 20 seconds...
New Replies:
By CSA on 23 September, 2008 - 10:08 am -
By CSA on 23 September, 2008 - 10:08 am -
1. My opinion should not matter.
2. Every turbine manufacturer/packager has different criteria...
By speedtronic on 23 September, 2008 - 1:28 am - Dear CSA,
So far you have been very nice as you have answered all my queries & I have gained...
I want to do cable sizing for process control instruments in oil & gas.
New Replies:
By Roy Matson on 23 September, 2008 - 10:04 am -
By Roy Matson on 23 September, 2008 - 10:04 am -
I don't believe there is a procedure it really comes down to site preference. The larger size e.g....
I'm looking for a linear actuator with a 12 volt or 24 drive but interfaces with a 4.8-6.0 volt RC receiver. It must have pretty much 100% duty cycle and have 35 lbs pulling force.
New Replies:
By Roy Matson on 23 September, 2008 - 10:03 am -
By Roy Matson on 23 September, 2008 - 10:03 am -
I recently used a bunch of Linak LA12 actuators
These are available in three different thrust...
Where can I learn WinCC?
New Replies:
By Cedric on 23 September, 2008 - 10:03 am -
By Cedric on 23 September, 2008 - 10:03 am -
You can go on SIEMENS AUTOMATION Web site. In this site, you have possibility to download demo of...
what is the mmaximum %IZ difference that we can still operate transformers in parallel?
We have four GE Frame9 gas turbines (MarkIV) that always run on base load. While GT is running on furnace oil, sometimes (at least once in 2 hours) heavy dark black smoke comes out of boiler stack (GT running in combined cycle mode) which lasts from 5 to 10 minutes & then becomes normal...
New Replies:
By CSA on 23 September, 2008 - 9:59 am -
By CSA on 23 September, 2008 - 9:59 am -
jojo,
You're right; I misread the post and didn't pick up on the multiple references to combined...
By speedtronic on 23 September, 2008 - 1:24 am - As far as soot blowing frequency is concerned, it is performed after every 12 hours of GT operation...
By Phil Corso on 23 September, 2008 - 1:19 am - Finally, a voice of experience!
Phil Corso...
Have a waterfall churning out 12KW from an induction generator. My local utility gave me a new electronic meter that records the absolute kWh. So now when I send them excess power they charge me for the privilege! My old spinning disk meter was more fair even with an anti reverse ratchet!
New Replies:
By Willim Hinton on 23 September, 2008 - 9:57 am -
By Willim Hinton on 23 September, 2008 - 9:57 am -
Rob,
Here is an off-the-shelf solution:
...
By Phil Corso on 23 September, 2008 - 1:16 am - Rob,
You are being charged by the utility because the calculation for power is equal to:
P...
Small SCADA project for electricity monitoring
New Replies:
By jjolly on 23 September, 2008 - 9:56 am -
By jjolly on 23 September, 2008 - 9:56 am -
You can use a sixnet mini ipm model 131 which has 485 ports and a single ethernet port and you can...
from the electrical department...
Terminal (load) voltage changes in single alternator due to change in driving torqueEffect of varying the driving torque of single alternator on load voltage (load connected is purely RESISTIVE).
New Replies:
By CSA on 23 September, 2008 - 9:55 am -
By CSA on 23 September, 2008 - 9:55 am -
shahvir, There is an excellent website, canteach.candu.org, which has some really good teaching...
By Phil Corso on 23 September, 2008 - 12:53 am - Shahvir and Blackstoneboy:
I'll gladly provide any information requested. Just contact me with...
Do Siemens S7-200 and S7-300 PLCs have a communictions module for DNP3? If not, how do I get them to talk on with the DNP3 Protocol?
New Replies:
By j.jolly on 23 September, 2008 - 9:52 am -
By j.jolly on 23 September, 2008 - 9:52 am -
I have used the Kepware DNP3 driver on several occassions... works GREAT!!...
JJ...
ICONICS vs. Citect to replace WinCC?
New Replies:
By j.jolly on 23 September, 2008 - 9:51 am -
By j.jolly on 23 September, 2008 - 9:51 am -
Dear Sirs,
First off I am a veteran citect programmer and plc programmer with over 20 yrs of...
Cross current in synchronized generators neutral cable
New Replies:
By shiju on 23 September, 2008 - 9:48 am -
By shiju on 23 September, 2008 - 9:48 am -
hi,
for reducing circulating current the voltage droop setting of your gensets should be same. if...
By SAA on 23 September, 2008 - 1:31 am - One of three Genset AVR has no Voltage Droop setting.
Yes, current starts flowing after Circuit...
I need to upgrade Paragon 550 implementation controling a chemical reactor.
New Replies:
By Don on 23 September, 2008 - 9:46 am -
By Don on 23 September, 2008 - 9:46 am -
I too am looking to upgrade from Paragon 550 to Paragon for windows (or anything else this side of...
from the Automation List department...
question on Modbus Holding register and input register data typewant information on the data type and formats for the Holding register and Input registers
New Replies:
By Glen on 23 September, 2008 - 9:45 am -
By Glen on 23 September, 2008 - 9:45 am -
There is a modified Modbus specification designed by Enron Corporation that uses 32-bit registers...
By Fred Loveless on 23 September, 2008 - 2:20 am - A single register is defined as 2 bytes, signed or unsigned data. IEEE Floats an signed or unsigned...
By giri babu on 23 September, 2008 - 2:09 am - Hi Issac,
Thank you very much for your reply. It is clear now for me....
By Michael Griffin on 23 September, 2008 - 1:35 am - If you use a register size of other than 2 bytes, it isn't Modbus. Any standard Modbus slave your...
I am interested in applying as a PE in electrical engineering.
New Replies:
By Russ Kinner on 23 September, 2008 - 2:22 am -
By Russ Kinner on 23 September, 2008 - 2:22 am -
Yes, the first of the 2 exams (Fundamentals of Engineering) covers all disciplines of the...
Four Pump Alternator in ladder logic
We want to establish communication between Yokogawa Centum DCS with a PC over serial link
New Replies:
By Simon Baker on 23 September, 2008 - 2:17 am -
By Simon Baker on 23 September, 2008 - 2:17 am -
Is the PC slave or master?
Are you talking about more than a protocol emulator running on a PC...
We are facing a problem of Mark V controllers <R>, <S>, <T> whenever lightening strikes near by electrical switch yard.
New Replies:
By VRVR on 23 September, 2008 - 2:12 am -
By VRVR on 23 September, 2008 - 2:12 am -
Dear CSA/CTTech,
I am encouraged by the responses and valuable inputs provided by you. I have...
Transmitter impulse tubing tapping on process line
New Replies:
By Roy Matson on 23 September, 2008 - 2:11 am -
By Roy Matson on 23 September, 2008 - 2:11 am -
It really depends on a lot of different factors. I assume you are referring to a horizontal line.
...
Troubleshooting Modbus RTU protocol ommunication on RS485 looping
Mark5 Exhaust Temperature Spread Calculation
New Replies:
By FrankRen on 23 September, 2008 - 2:02 am -
By FrankRen on 23 September, 2008 - 2:02 am -
Here is a picture, I hope it will help.
Exhaust temperature spread:
This function shows the...
I am new to this forum and facing difficulty with the ICS TRIPLEX Trusted PLC. Issue is related to firmware/build revisions on Processors and I/O Modules.
from the Control eng department...
Choosing a Distributed Control System for the Crude Oil and Natural Gas Extraction PlantDCS selection, SIS, Modbus, Profibus
Why do Client Builder and Configuration Explorer on the client side complain about "There are no available licenses" each time I try to start them?
can anybody give me info about the best institute which provides embedded software training in mumbai (its contact details, if possible)?
New Replies:
By Anonymous on 23 September, 2008 - 1:36 am -
By Anonymous on 23 September, 2008 - 1:36 am -
What you are saying is correct. Everyone tries to cheat students... to earn... Even IDEMI is having...
Why is % impedence important...
New Replies:
By Hussain on 23 September, 2008 - 1:36 am -
By Hussain on 23 September, 2008 - 1:36 am -
Our alternator voltage are 6 KV and exciting bus bar is 3.3 KV. Due to that we required 6/3.3 kv...
Redundancy feature of AC800M controller from ABB
New Replies:
By Rob on 23 September, 2008 - 1:32 am -
By Rob on 23 September, 2008 - 1:32 am -
PVRN,
Sorry, I hate saying that someone is wrong, but the general statement that all ABB AC800M...
One of the generators has leading power factor
Programming AB 1756-IT6I Thermocouple Module
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