Signal & Control Cables

Type "what is the difference between signal and control cable" into google.

And this is what you get

http://www.google.co.uk/search?q=what+is+the+difference+between+signal+and+control+cable&sourceid=ie7&rls=com.microsoft:en-gb:IE-SearchBox&ie=&oe=&redir_esc=&ei=6szXS8UlhfbSBMKX4f4H

For my interpretation I use the following means to separate the functions.

A control cable is one that I wish to use to transmit a control waveform through to create an outcome at the other end. Like sending a voltage down a cable to energise a relay.

A signal cable for me is like the cable coming back from the relay contacts indicating the state of the contacts (closed or open).

Another signal might be the output from the wires of a thermocouple where I am interested in the signal that I can sense coming from the cable. In the case of thermocouple wire, the voltage tells me something about what is being experienced at the other end and may cause me (or the equipment) to take some action.

Basically, I send a control and I sense a signal.

@Just an Engineer - Right on.

My view is as a user, rather than an electrical engineer:

- A signal cable is low voltage, low amperage that gives me information, like the room temperature.

- A control cable may be low or medium voltage/amperage, depending what's on the other end - like the off-on switch from the thermostat to the air conditioner to lower the room temperature.

Non-electrically speaking (yes, part of the world is still not 100% electronic )

- A signal cable could be the wire or rope that moves an old-fashioned metal door bell, or tells the cook in the kitchen that the dinner table in the dining room is ready for the next course (have to watch tv to know what this is today).

- A control cable could also be a mechanical cable that changes the position of the device on the other end, for example hand brakes on a bicycle.

OK?

JimmyCraig

This has been discussed few times in electrical forum. Here it is again:

Control cable: These are the cables which are used for electrical controlling purpose such as motor start/stop, schematic wiring, monitor open/close status of a contact and pressure switch sensor etc. Generally the maximum size of control cable is 12 AWG (most cases it is 14 AWG) and it may contain as many as conductors. The ampacity and voltage drop is minor concern for selecting this cable. Current flow through control cable is momentarily in most of the cases.

Signal cable: These cables carry instrument or communication signals (digital or analog). The signal cable is primarily used for communication and instrumentation purpose. Most common size of instrument cables is 16 AWG. The conductor of these type of cables are grouped either pair or triad or quad. The individual pair or triad or quad is shielded (or screened) to protect the signal from outside noise.

See these previous discussions on this topic:

http://cr4.globalspec.com/thread/51680

http://cr4.globalspec.com/thread/47405

- MS

Dear Sir/Madam,

Could you please enlighten me with how the BW500 calculates the zero and span deviation error. If we do a zero and span check BEFORE performing the actual calibration procedure, we get (eg) -0.59% zero deviation error, and (eg) -1.82% span deviation error. After performing the zero calibration, our span deviation error came down to -0.08% WITHOUT entering the span cal correction. This would mean that the zero error is not a linear thing whereby if there was a buildup of dust/material giving say a 0.5% error, then the indicated TPH at operating weight would be in excess of 1.5 - 2% depending on the mass on the scale. Is this correct? The way I see it, if you have a buildup that gives an error of say 2 TPH, then that error should be reflected all the way through, but if we believe the span deviation error, then this will not be the case. Your assistance in explaining this would be very much appreciated. Any one help please

Thanks in advance.

Lazaro

I truly wish that I could help you in that issue, but that's waaaay outside my experience. I was tempted to try to be a little humorous on this, but seems that you've replied to a different thread.

Hope that you find the answer you need from another helpful soul.