UPB and 3-Way

[upstatemike]

I notice UPB switches offer a companion switch for 3-way applications and I was wondering why you wouldn't just use another full switch and link it via software? Seems like this would be more flexible since you could always change the companion to a multi-button transmitter if you want to control more stuff from there.

 

[Steve]

Well for one thing people complain about the cost of UPB. So why put in a bunch of $70 switches when a $20 slave will do? If you need multibutton in all those locations I guess that would be a reason but if not then I would just use the slaves.

 

[PeterW]

The big reason is latency. With a UPB 3-way system you have a noticible delay between pressing a button and it turning on/off. That's a different delay to the wall switch latency though.. UPB signalling is actually pretty slow. It is faster than X10, but not that much better. I have a recollection that UPB's data rate is 240 bits per second, vs X10's 60bps. Of course, UPB command packets are much larger and are acked, so the round trip delay is still very noticible.

I don't know if I'd want to depend on UPB signalling in a high use area unless the ramp rates were fairly slow in order to mask the response time.

 

[upstatemike]

The big reason is latency. With a UPB 3-way system you have a noticible delay between pressing a button and it turning on/off. That's a different delay to the wall switch latency though.. UPB signalling is actually pretty slow. It is faster than X10, but not that much better. I have a recollection that UPB's data rate is 240 bits per second, vs X10's 60bps. Of course, UPB command packets are much larger and are acked, so the round trip delay is still very noticible.

I don't know if I'd want to depend on UPB signalling in a high use area unless the ramp rates were fairly slow in order to mask the response time.

I did not know there was transmission latency with UPB! I thought the only issue was the double tap delay on local control.

I guess if I can get past all the firmware updates that sticking with Insteon is going to be a better strategy for me.

 

[gduprey]

Hmmm - well, there isn't a transmission latency per se -- that implies (at least to me) some delay between the switch wanting to send an UPB command and actually sending it. UPB controls that are ready to send a command do so immediatly, assuming there is no other UPB traffic on the line (in which case they wait for the traffic to clear).

As for UPB speed, I had a house full (70+ switches) of X10 switches and in the last 6 months have switched over to UPB. I can assure you the speed difference is very noticible -- at least 4x faster than X10. With X10, you could often count to 2 seconds before a command that was being sent caused a switch to come on. With UPB, while there is a delay, I think it is less than 1/2 second and probably more like 1/3 second.

Where the UPB delay that people really gripe about comes from is that when you press a UPB switches "on" paddle, it waits for up to 3/4 of a second or so before sending out the UPB command (if any) and turning on the connected load. This is supposedly because the switch needs to see if the user is going to double tap (which could fire an entirely different action). It is annoying, though you do tend to get used to it (well, most folks). I beleive PCS/UPB implementers have heard enough from their clients on this that I'm hoping this will be removed in the future.

On the topic of 3 way, there are two likely reasons for using a dedicated slave vs a seperate switch: cost and time. THe slaves are a lot cheaper than another switch and that 3/4 second delay and then the 1/3 second UPB needs to send a command starts adding up to be annoying.

Granted, if you want a multi-button controller at both sides of the 3 way, you have to use 2 UPB switches, but otherwise.

I have both setups (slave switches -- 4, and 2 UPB switches acting in a 3-way arrangement -- 2). For where I used the 2 UPB switches as a 3 way, the delay doesn't matter (it's for turning basement lights out after leaving the basement). But for the other places (hallways and stairways), I would stick with a tradional slave switch.

UPB control has been flawless (especially compared to my X10 system, which I thought had been pretty solid, but in comparison looks poor) and the speed of control has allowed me to use motion sensors, hooked to my controller to trigger UPB lights and links/scenes very effectively. While everyones experience is, of course, different, I've not seen any problems in high traffic areas with UPB switches responding to use or being controlled remotely (via other switches, sensors, etc). I'd agree that in a high traffic 3-way setting, you'd be best with a standard UPB slave 3-way setup.

Gerry

 

[PeterW]

I can assure you the speed difference is very noticible -- at least 4x faster than X10. With X10, you could often count to 2 seconds before a command that was being sent caused a switch to come on. With UPB, while there is a delay, I think it is less than 1/2 second and probably more like 1/3 second.

You've described in detail exactly what I was getting at. It may be 1/3 of a second, but that's still an additional 1/3 of a second compared to the hard wired UPB or X10 slave switches. I used a table-top remote for a while to control the lights and the delay was apparent. Not annoying, but it was there.

I know well about the other delays and the reason for them, I have griped about it enough myself. It annoyed me every time they were used and I never got used to it. We had instant-on lighting when we had X10 based switchlinc devices. It was one of the final nails in the coffin for us and led to our UPB switches sitting in a box in the garage gathering dust.

When we switched to Insteon, I was relieved considerably that both delays were effectively gone. The delay due to differentiating a single vs double tap was gone (Insteon doesn't have built-in double-taps), and the remote control delay was gone. IMHO, while there is a very slight remote control delay percievable if you pay attention, it is as good as instant.

Now of course, if only the Insteon folks would fix the remaining annoying things.... Sigh.