How to connect PS3 to both routers with wired connection?

[#1]

This is in relation to my other post, (unable to connect to ps store yet everything else works fine) supposedly my inability to connect to the ps store may be fixed by connecting through a wired connection instead of the wireless method, my problem is when the plusnet engineer came to install fiber optic i was given two routers to use simultaneously, without using both i was told i would not be able to use fiber and not connect to the net either, so i tried making a wired connection to the first router, no detection, tried the second router, no detection. any ideas on how to make a wired connection to both routers simultaneously? thank you to anyone who may have an answer to this!
[Moderator's note by Jim (Oldjim)  All Caps removed from title as per Forum Rule

[#2]

with fibre one is a router and one is a modem, you can't connect your ps3 directly the modem.

[#3]

ok that makes sense, i can tell which of the two is the router. i'll try having another go at making a wired connection to the router. i'm just worried that having this second modem thing is preventing a detection, it worked fine when i had regular broadband with just the router on its own.

[#4]

my ps3 connects to the store and PSN just fine and I'm on fibre - though think I have a different router.
on ADSL the modem is in built in to the router.

[#5]

thanks for the replies guys, i'd rather hear others have no problems than get zero response. is it possible that some part of my ps3 is damaged and preventing access? i did have to reflow it the other night (fixing the ylod etc) but i've done it many times before and i'm pretty confident i was careful and didnt cause any damage. i would have thought if it is a result of something during the fix, how is it that i have only a problem with the store and nothing else whatsoever? do u think it's a hardware issue caused by some damage somewhere on the motherboard or is this likely to be a compatibility issue between my router/modem and the coding behind this new store? i will shortly be making a us-based account as their store hasn't updated yet, if that works i will seriously consider purchasing a us psn voucher online (i've discovered a trustworthy site that does this for situations like this as you can't assign a uk debit card to a us account), buy the game with that and then play it with my eu account. bit of a ballache but if i'm the only one around with this problem i can be certain sony won't help me out here. can't exactly see them releasing a new firmware just for my benefit