Cable in MIR Environment

[hewissa]

One of my clients wants to install a shielded MIR system in his veterinary hospital, while "modernizing" the rest of the hospital. The plans call for cat-5 cabling. I have been brought on board as a consultant on the project and immediatly brought into question the cabling.

I have moved to change the plans to a gigabit fiber environment since I feel the MIR, although shielded, would have and impact on standard cat 5/e/6 wiring. Especially those that are run close to the unit.

Any thoughts would be appreciated.

Thanks

Hewissa

MCSE, CCNA, CIW

 

[AvayaNovice]

MIR? Do you mean MRI?

If so...

Fiber I think would be excessive. ScTP might be sufficient, and if you place it in conduit... I think you'd be fine.

 

[jimbopalmer]

twisted pair ethernet uses differential signaling, so if a large spike apears, it is fine so long as it appears on both sides of the pair.

Cat 5 is an older standard, I would use Cat 5e or Cat 6
and stay at least 2 feet from the MIR (or MRI) machine with the cable runs

I tried to remain child-like, all I acheived was childish.

 

[hewissa]

Duh! What was I thinking...what you guys must have thought...that the vet was puting in a MIR Statalite....my bad. Yes I did mean MRI, the Magnetic imaging device. sorry about that!

I would go with the 6 option to ensure a gigabit network. Are you both saying that the cat6 should be in a conduit to protect it further. If so, the cost of the conduit would equal the cost of running just the fiber.

Judging from the plans this MRI is going to be in a shielded room, not sure what the shielding is, and I have never worked with an MRI before. As for the cables, they will be strung along,and above the system. Would that close proximity cause signalling problem? Won't the magnetic "charge" draw from the lines?

I appreciate your responses.

Hewissa

MCSE, CCNA, CIW

 

[jimbopalmer]

Fiber is not expensive and I ran a great deal of it before Cat 5 was finalized, but the cost of fiber ethernet cards never came down to the $10 it takes to get a copper ethernet card. one or two jacks near the machine may be useful but to do the whole office that way will set you back a lot in switches and NICs

I tried to remain child-like, all I acheived was childish.

 

[AvayaNovice]

The other thing is the cost of termination...

I don't know, I just really don't see copper as being too viable considering the easier nature of running copper, and the compliance with hardware.

Cat6 or Cat5e will run gigabit, no need for six unless you have some other outstanding requirement...

 

[hewissa]

I have had problems with Cat5e running gig in the past and found to avoid any issues, cat 6 is a sure thing. Since this is a reconstruction project I figure running 6 will last them for awhile. I forsee heavy traffic loads with video streaming for surgeries, up/down loading of large digital and MRI images and such.

So the megnetic current from the MRI won't have an impact on copper?





Hewissa

MCSE, CCNA, CIW

 

[AvayaNovice]

The twisted pair nature cancels out quite a bit, and if you run it in conduit, it'll have even more protection. I've run cat5e next to large electric motors, which have huge magnetic fields... as long as its twisted, you're usually in the clear.

 

[technome]

Mri machines produce tremendous electro magnetic force (EMF), so does arc welding. A close hit of lightning more than either, EMF bombs and nuclear explosions produce the ultimate emf capabible of destroying transitors, mechanical relays, basically any device not totally shielded. Enough BS

copied this from an another formum I posted it on.....

"In case anyone has ever wondered about emf pulses from nearby lightning strikes, power lines, lighting fixtures...

With Cat 5, the wire twist cancels emf extremely well. I have a client where very high current welding proceeded for 1 week, no more than 6 feet from a bundle of 28 cat 5 utp cables( in an unshielded wood raceway), much of the welding occurred within 12 inches. The server was also within 6 feet. End result, not one computer in the system had any machine or program lockups, no data errors.

This situation occurred in an office structure built on a large steel barge, located in the New York harbor. The wire were running parallel, for the full length of the wood structure, to the welding. Every monitor in the building was suffering from the constantant emf pulses from the welding arcs, the screens would actually become unreadable. The owner became worried about the monitors fading in and out. After 4 days of welding, he called me to the site.
If I was asked about the situation before the welding started, I would have advised him to close shop for the week. But after 4 days, I actually had full faith in the wire twist cancelation; I was more concerned with the monitors surviving the week. "

Since this is a hospital situation, perhaps this MRI or another device could produce a frequency which is not canceled out ( far fetched but..). To be absolutely safe and to rule out any possibility of extraneous signals entering or leaving the MRI unit I would run fiber cable to the unit. From my understanding, MRI rooms (walls) are shielded, if this is the case, the cable from the MRI room would be the only fiber cable needed. Personally I have purchased pre terminated cable lengths over 200 feet, so the expense of bringing someone in just to terminate the fiber cable can probably be eliminated. If the fiber cable is in areas where physical damage could occur ( out in the open, such as along a baseboard), I would run it in emt