Recent content by madddog

DADFAP you refer to Baker Hughes Centrilift and the fact that you have experience in pumping power to a 330HP submersable pump. I need to find characteristic curves on any VFD rated ac motor rated to 100HP. If they are available from the Baker website I sure was not able to find them. Any...

Thanks for all the great input and poetix99 you are correct but I have to begin by defining the heat rise contributed by the insulated copper wire first before I can start calculating the heat flow through the different layers of inslulation. JEngineer you are also correct but can you lead me...

Thanks jbartos Your second link helped but also confused since it relates to PC board copper runs. I need a solid reference for this problem. Anymore help would be greatly appreciated.

I need the equations that define the temp rise of a #10AWG insulated wire carrying 11.23 amps. I am designing an 10,00ft umbilical cable that will power two 150HP electric pumps. The heat rise per foot will determine the maximum number of layers on a cable reel, ie overall reel size. Thanks

This sounds pretty simple to you heat transfer qurus but to someone who doesn't do this on a regular basis, HELP. I need the equations to determine the temperature rise of an insulated #10AWG copper wire carrying 11.23 amps. I am designing an umbilical cable that feeds power to two 150 HP...

Thanks Grimmer, My problem with your solution is that my input amps have to be referenced to ground and can not float up. By using two separate 200 ohm resistors in parallel runs from the sensor I actually split the 4-20mA in half. Each resistor then "sees" 2-10mA and generates...

I purchased a data acquisition board from the ADAC company. The board is a 5516DMA. Along with the board came software drivers written for LabView. I am running LabView 5.1. After loading their software I began to run several example .vi's. I have confirmed that the software (.ini, .con)...

Actually I do mean switch for the reason you stated, isolation of networks.

Can anyone lead me to an internet site that has a schematic of a 4 or 8 port Ethernet switch. Thanks

Thanks for the replys. Unfortunately I have one sensor powered by two independent 24v power supplies that must be monitored by two data acquisition systems, one or the other is the backup. The systems are located about 100ft apart. Each power supply has a diode on the + output inturn...

Normally the return wire of a 4-20mA sensor terminates with a 100 ohm resistor at the input to a data acquisition system. My question is can you have two return wires each terminated with a 200 ohm resistor monitored by two data acquisition systems. The parallel resistance would equal 100...

Thanks for the info Fredb. Are you familiar with VSDs? I have to assume that the second person's response comes mainly from the fact that any system used in a residential manner MUST be "user proof" since you are dealing with users typically with no experience in electrical...

Has anyone had any experience with decreasing the electrical load of a residential HVAC system by using a varible voltage drive to control the speed of the compressor over the heat cycle of a day?

My problem is that my system was not sized for the added heat load of a townhouse end unit. All systems were sized as a middle unit with other units on both sides, two "cool" walls on each side. Since my unit is an end unit I have only one "cool" wall and one HOT wall. My...

Basically I want to measure the coil temperature averaged over the top third and bottom third. Then spray conditioned water at various locations on the outside of the coil and measure the dip in temp as the water evaporates, removing heat. Measuring the temp with sensors in series / parallel...