Does a PG9WLSHW8 really need EOL resistors?

Just bought a IQ4 panel and PG9WLSHW8 Hardwire takeover from you and about to transition from an old 2gig GC2 panel with a separate takeover having 8 single-pair wired NC zones. It seems the old wiring does not have any EOL resistors connected to the takeover.

So is it really necessary to splice resistors in for the PG9WLSHW8? The installation guide first mentions both NC and NO schematics with no resistors on pg 14 as if supported but then also mentions SEOL and DEOL schematics later.

So does the PG9WLSHW8 properly learn those NC contacts with no resistor to save the hassle? After all, there seems little point of a resistor near the takeover in order to detect the (rare) occurrence of a short downstream. For that the SEOL should be up close to the sensor (which would be a huge hassle), correct?

On that note is there such a thing as a magnetic reed NC window sensor that cleanly integrates DEOL resistors within it so you can actually sense the resistive difference between a shorted or even broken wire to the sensor?

And is there any kind of inexpensive zone expansion option or do I have to buy and mount a 2nd complete PG9WLSHW8 box just to add a few more zones (so I can separate out some windows all on the first floor currently wired in series)?

I just installed an IQ4 and 2 x PG9WLSHW8 this weekend and the answer is NO, resistors are NOT required.

When defining the sensor, you have “Input Mode” options for “Disabled”, “Normally Open”, “Normally Closed”, “End of Line”, and “Double end of Line”. Setting to “Normally Open” or “Normally Closed” is what you would use if you do not have resistors. Setting “End of Line” or “Double End of Line” would use if you are installing SEOL or DEOL resistors.

When using auto learn or manually adding the zones, they will default to “End of Line” for the Input Mode, so you just need to manually change it if not using a resistor.

I actually have a mix of zones with and without resistors and they all work fine as long as they are properly programmed in the IQ4.

As far as expansion goes, I happened to come across this post this weekend that references a DSC HSM2108 Zone Expander being able to be used (up to 4) with a PG9WLSHW8 but couldn’t find any other details about it specific to Qolsys use: New Equipment Release Dates? (IQ4, POE 4K w/ Audio, PowerG higher limits?)

I actually purchased 2 x PG9WLSHW8 before even thinking about expansion capabilities on a single one so kind of a moot point for me as I won’t need to go beyond 16 wired zones.

As far EOL resistors in general, they should be at the contact side, not the panel side if you want the benefit of what the resistor provides. To meet UL the resistor needs to be at the end of the line not at the panel, but most residential installers don’t care about meeting UL, so it’s easy to place the resistor at the panel if the panel requires one. There’s also the fact that placing a resistor at the contact in a typical residential install using mini reed contacts is just not viable from a packaging/space/aesthetics standpoint, so that’s another reason you generally see the resistor at the panel when it’s required. If the panel doesn’t require a resistor, then no need to even bother unless you want the benefit of the resistor and are installing it in the appropriate location.

GRI makes contacts with built in resistors. I have not used them but I looked into retrofitting my existing contacts and decided against it. The alarm wiring in my home is now 18+ years old and I’ve never had an issue with any of my wires including replacing my windows and re-using existing wires (not contacts though). The GRI ones only cost about $3-4/more over the typical Honeywell/Ademco reed contact and are all SEO. I personally haven’t come across contacts with built in DEOL, but they may exist:

Additional info on the zone expanders. Support for this was just announced in the IQ4 4.1 firmware details: Qolsys IQ Panel 4 Firmware Release Information - #4 by tyler

This indicates that firmware 1.2 is required on the PG9WLSHW8 though, and the ones I ordered last week shipped with 1.1 and I’m sure your unit does as well.

I found this older post where someone asked how to upgrade an existing unit to 1.1 and was ultimately told “we can’t help you”. I have inquired in that post about Surety’s official stance on how their customers can keep their PG9WLSHW8 modules up to date: How to update PG9WLSHW8 to V1.1? - #7 by Carlisle

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When using auto learn or manually adding the zones, they will default to “End of Line” for the Input Mode, so you just need to manually change it if not using a resistor.

Thx! So it simply is a matter of an IQ4 setting (which I have yet to set that up given takeover is supposed to be wired and ready first). Reading that the older IQ H16 takeover required resistors I just wanted to make sure leaving them off did not damage my new takeover because of an old-school current draw or something.

GRI makes contacts with built in resistors.

OK, so guess I didn’t realize you have to custom order the resistor size because of an apparent lack of industry standardization here(?) Sorry, rather new to this :grinning: Just seems like something obvious to standardize. Altho I’m seeing some reed contacts long enough with lugs that you might be able to at least pack a couple of tiny 1/4w 5.6K resistors off the lugs for DEOL. Someday for a different house …

This indicates that firmware 1.2 is required on the PG9WLSHW8 though

But of course my brand new takeover still says v1.1 f/w on the back sticker :roll_eyes:

Welp, I see the HSM2108 is just $22 on Amazon. That’s a lot cheaper than another $120 takeover and having to mount another whole box on the wall with another power brick just for a couple/few more zones. So figured I’ll just order one and see what happens if anything on v1.1. If likely nothing, I re-splice the zones.

Funny thing is I once bought that DSC data cable for an old house on DSC some 12 yrs ago that was a pain to program by hand. Cable was DB-9 when laptops used to have those. I vaguely remember the DLS app then only worked on WinXP and people posted it along with the f/w images with a hacked DLL to get past DSC’s partner check :wink:

The IQ 16-F Hardware’s aren’t really older, they are just different. They are Qolsys S-Line vs the IQ Hardwire PowerG (PG9WLSHW8 ) being a PowerG based. The Hardwire PowerG is more sophisticated in what it can do/support, but it also only 8 zones native vs. 16 in the S-Line module. While you now have an option to expand a single PG9WLSHW8 to support 40 zones, you still have cost associated with the expansion modules and an enclosure to put them in.

You can also setup the IQ4 before your Takeover is ready. I removed and re-added the Takeover a few times (wanted the zone number ID’s in a certain order) and also completed powered done the modules numerous times. You won’t harm anything by not doing it in a certain order, other than perhaps

If you want to go DEOL then you would need to custom order GRI ones with 5.6K Ohms resistors. There’s probably a minimum order quantity for that as well that may not make it viable. If you go SEOL then you can use their standard 1K or 2K Ohms options as the PG9WLSHW8 will work with 1K to 10K Ohms resistors. I am actually using 1K Ohms on my contacts with resistor because that’s what was required in my prior panel.

There’s also a question of how the IQ4 would handle reporting on SEOL vs DEOL. SEOL is reported by the PG9WLSHW8 as either “Alarm” or “Secure” but DEOL reports as “Alarm”, “Secure”, “Trouble”, and “Tamper”. I would think the IQ4 would report on these as described since those are 4 states it can report on it general, but the documentation available when it comes to IQ4 + PG9WLSHW8 combo together is very lacking on this kind of technical detail.

You can fit a resistor into a non-lugged reed contact depending on your wire. Most reed contacts are rated for 18-22 AWG wire so if you have 22 AWG wire you can get a resistor in with it on the compression terminal no problem. It’s just rather ugly having a tiny resistor or two hanging off your contact. If you paint the resistor to match your trip it wouldn’t be so bad.

Same here, and I have 2 that I ordered last week.

I’m sure it’s simply not going to work without firmware v1.2 but for $22, doesn’t hurt to try.

Also, if you intend to put a battery in the PG9WLSHW8 (which you really should do) then you are going to need another box for the HSM2108 in general, so even if it works or you get upgraded somehow, you would need another enclosure unless you forgo battery backup.

There’s just no room inside the box otherwise. Here are my two installed units:

I did some quick research this morning and it’s still the same cable where you would need USB to DB-9 unless you had an old laptop with DB-9. Good news is they added Windows 10 support in v1.62 and it’s even .NET 4.0 based, so it seems as if DSC has been modernizing the supportability of the software: DLS5 Wiki

Actually, those tabs on each side of the battery are exactly where you clip in up to two HSM2108 expanders. Quite the tease when you clip in the expander then wire it to the Corbus, but realize the PG9 has outdated 1.1 firmware and those expander clips are just as useless.