Top-of-tower WS-12-250-DC Box

[jbaird]

Here is a new top-of-tower box that we are deploying at a bunch of our old water tank sites. Fiber/DC up the tower.

[sirhc]

Could you label all the devices in the box and their purpose for educational purposes?

Also please connect the chassis ground wire to your ground bus as the 2 through hole studs may not get a good connection to the chassis from the powder coat. If the DC switches are not connected to Earth Ground then ESD protection is rendered inert.

[jbaird]

Could you label all the devices in the box and their purpose for educational purposes?

Also please connect the chassis ground wire to your ground bus as the 2 through hole studs may not get a good connection to the chassis from the powder coat. If the DC switches are not connected to Earth Ground then ESD protection is rendered inert.

Starting from the top-left, we have:

1. SyncInjector 100 - used to power and provide sync for FSK radios on this site.
2. SiteMonitor II - used to monitor 24V and 48V rails and control the SyncInjector
3. 24V fused bus - powers SyncInjector and SiteMonitor
4. Traco TCL-060-DC 48-24VDC DC-DC converter - used to convert 48V which we run up the tower to 24V for the SyncInjector 100/FSK
5. 48V fused bus - powers WS-12-250-DC, SiteMonitor

Yeah, we'll connect the WS to the ground block. A few sites will be completely floated, so we'll likely not ground anything there. The equipment/antennas, etc are all isolated from metal using rubber matting. I'm debating on not using surge protectors on these sites at all, since the ground will be floated.

[sirhc]

You know, you could power the 24V and 48V stuff from the WS-12-250-DC units if you made up an RJ45 jack using all 4 pair and plugged into 1 of the special ports 1-4 that are capable of 24VH and 48VH.

Thus you could power the SyncInjector 100/FSK from the WS-12-250-DC.

This way you run up 1 power cable and it does not matter about voltage drop as the WS-12-250-DC will correct for it and you will always get 24V and 48V (50V actually from the WS-12-250-DC. When a port is set to 24VH or 48VH you get 1.5A of capacity which could power those devices and you have the ability to power cycle them if need be.

Just a thought.

[jbaird]

Yep - the only reason we aren't powering the SyncInjector off of a port on the WS is because we don't have any spare ports at this particular site. On sites where we have spare ports we could use a POE-PowerTap [1] to extract power from the WS port to power the SI.

[1] http://tyconpower.com/products/files/PO ... _Sheet.pdf

[sirhc]

That is an excellent product, too bad it does not use all 4 pair as that would allow up to 1.5A with our VH ports

Using 2 pair only provides .75A (safely), drawing more than 1A will damage our Ethernet Transformer