How to Wire Motions using Elk Expansion Cards

[Smarty]

Question for the security guys....

I have a remote box that has 3 Elk expander cards in it and an Elk Data Hub. This hub will then connect back to my utility room where the main board is located.

My question concerns the proper way to supply power for the glass breaks and motion sensors.

I plan to run some 18/2 from the main board to the remote box. I will connect this to a "voltage bus" that I will secure inside this remote box. I plan to connect the ground of the bus to the neg (ground) of the cards. I plan to tie all the negatives together. I will then use short lead wires to connect the posative of the bus to each motion sensor.

Is this a proper approach? Is there an easier way to do this? All my sensors have 22/4 type wire between them and the panel.

Thoughts???

 

[BraveSirRobbin]

Well what this "crusty old white guy" would do in this situation is use a power distribution module such as THIS at the remote location. That's an awfull lot of connections at a "remote" location to not have some type of "fused" distribution to the modules. You can "double up" on some of the modules outputs if needed.

Also, you don't specify how many sensors you are hooking up, but with that many expansion cards I'm thinking it may be a lot. Make sure you add up all the current draws of your "remote" glass breaks and motion sensors and add them with the load which exists in the main box to make sure your present Elk power can handle it (don't forget sirens and keypads also).

If not, you may want to get an external power supply at the remote location.

Also, I would fuse the 18 gauge "hot" wire with an in-line fuse (at the voltage source), just because I'm paranoid (I don't like long power runs that are not fused at the source because you never know what could happen with all that length of wire in the future).

If you need any more clarifications/help just ask!

 

[Spanky]

Measure the voltage at the remote input expander and make sure it does not drop below 12 VDC.

 

[bmil]

(butting in rudely..)

I am looking to do something similar (remote box with an M1XIN, M1XOVR and M1XRF). Off of these will be several glassbreaks, PIR's, gas detector and maybe a couple of Pizzo's and other relay attachments.

Can a PD9 in this remote box just be used to power the PIR's etc. or can it actually replace the 2 power wires on the M1 bus and also power the expansion cards and M1XRF themselves ?

I wasn't sure if the power wires are an integral part of the 485 data bus protocol or just used to get power to each expansion device.

Thanks...

 

[BraveSirRobbin]

I don't see why it couldn't power the expansion boards as well, but I think I'll let Spank verify this!

Also, you realize that the PD9 is not a power supply, it is just a fused distribution box for a power supply's output. In other words, you want to make sure no matter what power methodology you use, insure it is battery backed (especially when using an external one). I like the Elk external supplies and they have a kit which includes the supply as well as the battery. The Elk power products are bullet proof and offer great protection as well (accidental shorts, etc...).

 

[Digger]

If you use an additional power supply (with battery backup of course) make sure you tie the commons (black wires) together.

 

[BraveSirRobbin]

If you use an additional power supply (with battery backup of course) make sure you tie the commons (black wires) together.

Will you really need to do this? The communication bus carries it's own reference (i.e. separate from the power supply ground) so I'm not sure if this is required. Also, you aren't "referencing" say an analog input voltage from the remote box to an acquisition A-D in the main box.

I might be missing something though, thus the reason for asking!

 

[Digger]

Its not stated in the Installation Instructions but it is required so that devices powered by the aux power supply will communicate correctly with the M1.

TECHNICALLY if you are just powering PIR's it would probably be ok. The zone expanders.... definitely need to be powered by a supply with a common tied to the panel.

It is actually a common (pun intended) requirement for most manufacturers systems.


SPANKY can chime in............

 

[rfdesq]

Tying the negatives together is not a rumor. I have a hand drawn diagram from ELK representative Kurt at an EHX show a couple of years ago that shows it.

 

[bmil]

Thanks all..

I'll make sure I tie the remote pwr supply neg. and the M1 bus neg together.

and yes BSR, I had planned on powering the PD9 with something like their P624 or one of their all-in-one kits in a can so I have a battery backup. Thanks.