Directv SWM Installation Demystified
This is an article posted by Justin Williams a member at The High Def Forum that pretty well explains the wiring of a SWM system. Used with permission.
First off SWM stands for Single Wire Multiswitch. What that means to you the customer is you donâ€™t need to run 2 lines to a DVR. You can also use most existing wire, connectors, wall plates etc versus the standard KAKU HD install that would require you to use new RG6 cable, new wall plates, and two lines to all DVRs. The only CON to SWM is that you are stuck with 8 tuners or less. (DVRs count as 2 tuners)
How do I know if I have a SWM system already installed or not? Take a quick glance at your dish. Are there 4 lines coming down the dish or only one? (Now some may have 2 lines, or 3 lines coming down. This is because the installer was too lazy to run 4 lines off your dish as required by DTV during installation.) A SWM install will have only one line coming off the LNB. It is important to note that the actual “look” of the “eyeballs” will be different for everyone no matter what type of system you have. This is due to DTV using different companies to build the LNBs. So don’t go by the look of the “eyeballs”, go by the wires coming down.
This picture shows to the two different LNBs. The one on the left only has one wire (SWM), and the standard KAKU on the right has 4.
Normal KAKU HD systems are powered by the receiver. The receiver will send a max of 18v up the line to the KAKU. SWM needs 20-21 volts to operate, so you will have to use a SWM Power Inserter to â€œsend upâ€ the required 21v. Here is a picture of the SWM power inserter. Notice that the PI (Power Inserter) has a red and white port. The red port will send power up the line to the LNB, and the white port will send the signal to the receiver.
Every install is a little different depending on the house, and there are 2 different ways to wire the system. I will explain both. However, before you get started you will also need a SWM Power Passing Splitter. These come in different varieties and all cost the same, so I just use the 1X8 in case of future expansion. The SWM splitters come in 1X2 (one in, two out), 1X4 (one in four out), and 1X8 (one in eight out). Below are pictures of a 1X4 and a 1X8 respectively.
You will notice that there are red ports and white ports on the splitter. The red ports pass the 21 volts needed to power the LNB, and the white ports will not. One red port goes to the LNB, and the other goes to the room where the SWM Power Inserter is located. It does not matter which red port goes to the LNB and which red port goes to the PI. The white ports go to any room where there is a SWM capable receiver. (Standard Receiver of D-12 or higher, DVR of R-16 or higher, HD DVR of HR-20 or higher, HD Receiver of H20 or higher) Any older receiver will not work with SWM.
As I mentioned there are two different ways to wire the SWM system:
The first method is the one I prefer. This is where the Power Inserter is located AFTER the SPLITTER and behind a receiver. However the only drawback to this method is that if the PI is unplugged it will make all the receivers in your house go SFSS (Searching For Sat Signal). It is VERY important to NOT plug our receiver or the PI into a power strip/surge protector. I have seen numerous service call solved by simply plugging it directly into the wall. Here is a diagram of this type of install.
The second method is where the PI is located in the attic BEFORE the SPLITTER. You will have to have a plug in the attic to wire this way. The only negative to this method is if all of your receivers are SFSS you will have to get in the attic to check for the little green light on the PI to ensure it has notâ€™t failed. When using this method you do not need to worry about red and white ports on the splitter. This is because the 21 volts are being sent up directly from the PI. The only thing coming out of the PI and going to the splitter is signal.