atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Security, Alarms and Paging New insatall DSC a couple of issues

new install on a DSC PC1555MX and when I powered up , nothing from the keypad . cabling all seems to be correct , I followed the instructions hooked the battery up first then the power . went to the keypad blank .

checked for power at the outlet and it was good .

any thoughts ?

bad board ?

bad keypad ?

second when setting up zones with N/C contacts why would I want to use the resistors ?

it gives me the choice of using a 5600 resistor or not

whats the reason /advantage in using them ?

On first time power-up, the AC must be present otherwise it will not turn-on (battery will not matter). With a volt meter, double check the 16VAC on terminals 1&2.

Also, those panels have fuse-less protection. Any shorts on the 12VDC "aux" or keypad will cause it to appear dead. Remove all DC lines and start with only the keypad and work your way up. You can also meter the red and black at the keypad to see if the DC is present.

The EOL resistors are a good idea, but they will only work if installed at the device, not the panel. The obvious benefit is nothing can short the line and "fool" the panel into thinking everything is okay, be it man made or building induced. That panel can indicate a short to building ground as well and report that to the monitoring station if required (this only works with EOLR in use).

Cable shorts can occur even down the road. I've seen misfires with the T18 staple gun cause a short a couple of years later. Also building settling, nails, and duct work shorts.

On normally open devices, the resistors constantly supervises the wire. On this type of zone, a broken wire could go unnoticed until it's too late.

On contacts, the resistor can be a PITA, but you get good at concealing them. You can also order contacts with the 5.6k built right in to them.

A little trick for concealed contacts that I do;
using quad wire for the contact, wire the contact up on yellow/black and B-connect or twist the red/green together (bumble-bee/Christmas tree). At the panel, install the resistor between the red/black with B's and wire the yellow/green under the zone terminal.

If you think about this, the resistor is still at the end-of-line, even though it is taking advantage of the room in the panel box!

thanks Simon

makes sense , I did check the AC outlet but didn't check the power at the panel

it was getting late and I had had enough for one day
finally got it all wired , powered it up and it was supposed to WORK !! .

I have been doing this ever since you explained it to me..works great!

We always put the EOL's in the panel on the fire alarms we install using the same method. I HATE walking around searching for the EOL on a system someone else installed and there never is any paper work left behind.

Sometimes I think companies do that on purpose so the customer will grow tired of the time it takes for a new vendor to get acquainted with the layout of the system.

Skip, along with the advice Simon gave you, you may want to hook the keypad directly to the motherboard to make sure it's ok. But it may also be the motherboard if it doesn't work but this will eliminate the cable entirely.
You may have to take the keypad and panel back to the supplier and have them tested. :confused:

We always put the EOL's in the panel on the fire alarms we install using the same method.

Dang, you guys are allowed to do that? It's against code here on fire panels. We aren't allowed to bury the EOL though so it is always on a labelled wall plate.

Another trick on DSC; if you don't have the 16VAC available for some reason but want to power the panel up and run it from the battery - just take a couple of jumper wires and feed the 12VDC battery into the AC input terminals (1&2, polarity doesn't matter) for a couple of seconds. The panel will now run on the battery input.

back on site today , I took the keypad and wired it directly to the panel , display came up , went through told me what zones where trouble , (doors windows open )

tried programing and it would let me into programing but didn't seem to let me enter anything. finally display went blank , just yellow trouble light .

I powered down and removed the battery thinking it might clear it

powered back up same problem so I pulled it of the wall and brought it back here to work with .

for the n/c zones I can just bridge them , Right ?

Skip..you can bridge them with an EOLR

If this is an LCD keypad and you have it wired up directly like T.T. mentioned, with no display at all, sounds like a bad keypad (I've had it happen).

Skip, the zones are always going to come up in trouble on that panel at the initial power up because there is a fire zone enabled by default and the zones are also set up for EOL's by default and it sounds like you are trying to use normally closed loops and switches.
Edit: I was mistaken, this panel does NOT have a fire zone programmed by default. Sorry for the false information.
It sounds as though you are entering base level programming successfully but you aren't quite entering the correct commands and the panel is timing out of programming.