Astec 49DV Fault

Ivan E

Hi,

My Astec 49DV has been going off in the last two days for no apparent reason. It's not showing any fault in the display and it's the same zone that's going off.

I have put it into engineering mode and pressed 11 to see if it showed any faults there but it shows everything working.

Any ideas on what it can be?

Thanks.

KoolKid

Probably a faulty sensor or contact on that zone. What does it show on the screen when you disarm it after an activation.
In engineer press 10 and go back through the log.

Ivan E

Thanks Koolkid for the reply.

It says Zone 1 contact. So I know what's setting it off. Just not sure why. I was assuming maybe the contact is faulty but i would have thought I'd see an error on the panel indicating a fault.

Going through the log I also see this:

2 set F3 telecom
1 set FTC
1 set F6

Not sure if that means anything or just that it went off and made the call.

KoolKid

FTC is Fail To Communicate . Meaning the call was not made successfully.
A faulty contact or sensor will not show up in open zones etc as the fault is intermittent its ok when you set the alarm but the alarm may activate a while after being set.
If the log is saying zone 1 contact all the time there is a faulty device on connection on that zone.

Ivan E

So just replace the contact then?

I presume that's straight forward enough. That a generic contact (ebay) will do and I just replace the existing one with that?

Do I need to completely shut down the alarm to replace it if that's the case?

KoolKid

To use a standard contact with Astec you need to wire a 680ohm resistor across the contact. 340 ohm if its an entry zone.
Is there only one contact on that zone? I would also be checking all connections & joins on that loop.
No need to power down the system when replacing a contact.

Ivan E

Yeah, I think there's only one contact on the zone and yes it's an entry zone. The contact was put in around 3-4 years ago by someone who knew what he was doing.

So I am just trying to gauge is it something i can do myself easily. I managed to follow the instructions in here on how to replace the battery previously. Hoping this is as straight forward. I was thinking I could just reuse the existing resistor there assuming there is one. But I suppose that could easily be the source of the issue too.

Steps then would:
1. Unscrew existing contact.
2. Connect the new contact the same way.
3. Check any other connections on that route.

or is there something else I need to watch for that could do damage?

Ivan E

Yeah, I think there's only one contact on the zone and yes it's an entry zone. The contact was put in around 3-4 years ago by someone who knew what he was doing.

So I am just trying to gauge is it something i can do myself easily. I managed to follow the instructions in here on how to replace the battery previously. Hoping this is as straight forward. I was thinking I could just reuse the existing resistor there assuming there is one. But I suppose that could easily be the source of the issue too.

Steps then would:
1. Unscrew existing contact.
2. Connect the new contact the same way.
3. Check any other connections on that route.

or is there something else I need to watch for that could do damage?

KoolKid

Pretty much yeah.
If the existing contact is an Astec one then the resistors are built in so no so easy to re use them.

altor

Ivan E wrote: »

Yeah, I think there's only one contact on the zone and yes it's an entry zone. The contact was put in around 3-4 years ago by someone who knew what he was doing.

So I am just trying to gauge is it something i can do myself easily. I managed to follow the instructions in here on how to replace the battery previously. Hoping this is as straight forward. I was thinking I could just reuse the existing resistor there assuming there is one. But I suppose that could easily be the source of the issue too.

Steps then would:
1. Unscrew existing contact.
2. Connect the new contact the same way.
3. Check any other connections on that route.

or is there something else I need to watch for that could do damage?

If using a global contact to replace you will need to use a 340 ohm resistor across the contact.

Ivan E

Thanks Altor. It was actually you who installed it 3 or 4 years back I think

I removed the cover and I see 4 wires with two of them going into some sort of blue block in the contact. I am not sure if that's the resistor. I have a picture of it which I can try and post later. Not sure if you remember that type of contact.

KoolKid

If it's the blue blocks sitting to the side they are usually just spare block connectors. Astec sensors would have the resistors built in.
Anyway if you post up a picture we can tell you for sure.

altor

Ivan E wrote: »

Thanks Altor. It was actually you who installed it 3 or 4 years back I think

I removed the cover and I see 4 wires with two of them going into some sort of blue block in the contact. I am not sure if that's the resistor. I have a picture of it which I can try and post later. Not sure if you remember that type of contact.

If its an Astec system then more than likely the one with a blue dot.
You would need to post a picture t be sure.

Ivan E

Not sure of the quality of this but hopefully it gives you some idea

KoolKid

Yes that is an Astec contact. If you are replacing this with a standard contact you must wire a 680 ohm resistor across the contact terminals.
If you stuck for sourcing one give me a shout. I've bags of them.

altor

Ivan E wrote: »

Not sure of the quality of this but hopefully it gives you some idea

Its an Astec contact alright.
The only way of knowing if the sensor is faulty is by using a mutlimeter to test.

Ivan E

KoolKid wrote: »

If you stuck for sourcing one give me a shout. I've bags of them.

The contacts or the resistors?

altor wrote: »

The only way of knowing if the sensor is faulty is by using a mutlimeter to test.

What exactly am I looking for here? It seems to work for a while and then just go off.

KoolKid

You would need to check the resistance on that whole zone using a multimeter.
Remove the end of line resistor.
Connect the leads from the multimeter to the pair for that zone at the panel.
Set the meter to 200 ohms and make a note of the reading. If there is nothing else onon that zone and it's only a short run the zone should read no more than a few ohms.
If you open and close the door and tap the sensor it should always return to the same value. If reading sticks up at a higher level or jump around disconnect the device and close off thethe pair at the sensor. If the reading then drops back it's the device that's at fault.

altor

Ivan E wrote: »

What exactly am I looking for here? It seems to work for a while and then just go off.

You wont be able to visually see anything. Only using a meter can you test the contact. Id follow the above but as its a contact tapping the sensor will have no bearing on the reading. Opening and closing the door is what you should be looking to do while testing the contact with the meter.

KoolKid

altor wrote: »

but as its a contact tapping the sensor will have no bearing on the reading.

It will if the contact is faulty. On a good contact you may see no change but I have found plenty of faulty contacts by tapping them while checking the resistance.

Ivan E

Thanks lads, I’ll try that tonight.

If it is the contact, can you still get Astec contacts or is it a case of just going with the standard ones and using a resistor?

KoolKid

A standard contact with a resistor is probably your only option.

Ivan E

Sorry, stupid questions to follow:

KoolKid wrote: »

You would need to check the resistance on that whole zone using a multimeter.
Remove the end of line resistor.
Where would I find that? Is that the blue block inside the contact?
Connect the leads from the multimeter to the pair for that zone at the panel.
There are two wires connected into the zone in the panel. Do I turn the alarm off, remove the battery contact and take the two wires out of the panel?
Set the meter to 200 ohms and make a note of the reading. If there is nothing else onon that zone and it's only a short run the zone should read no more than a few ohms.
If you open and close the door and tap the sensor it should always return to the same value. If reading sticks up at a higher level or jump around disconnect the device and close off thethe pair at the sensor. If the reading then drops back it's the device that's at fault.

I took a look today when I came in. There's two wires, blue and yellow going into the panel at the zone causing the trouble. These wires seem to go into the contact then. If I check for a reading off these wires at the panel, I am not getting anything but I didn't remove the end of line resistor so either it's that or I am doing it completely wrong.

KoolKid

If you didn't remove the end of line resistor then the meter will have to be set at 2k rather than 200 to get a reading.
If you remove the end of line resistor & wire the 2 cables to each side of the block then disconnect the pair & the panel and meter it out at 200 ohms you will get a much more accurate reading.

Ivan E

Right, it's just I don't know where the end of line resistor is?

Also I should be removing the wires from the panel and measuring there? I also should be turning off the alarm and battery?

KoolKid

If the resistor is not in the panel or that sensor then there is probably other devices on that zone. You disconnect the zone from the panel to measure the resistance.

altor

Ivan E wrote: »

Sorry, stupid questions to follow:



I took a look today when I came in. There's two wires, blue and yellow going into the panel at the zone causing the trouble. These wires seem to go into the contact then. If I check for a reading off these wires at the panel, I am not getting anything but I didn't remove the end of line resistor so either it's that or I am doing it completely wrong.

Are you sure that is the only sensor on that zone if the Resistor is not in the sensor or the panel?

altor

Ivan E wrote: »

Also I should be removing the wires from the panel and measuring there? I also should be turning off the alarm and battery?

Yes, the wires need to be removed from the zone in the panel and connected to the meter.

There is no need to down power the system to do this, if the alarm activates just enter your user code to turn off the alarm or put the system in engineer mode using the engineer code before opening anything.

Ivan E

Sorry lads, I just copped something. I was looking at the original install notes attached to the panel. I have forgotten I had got a new window put in since. Looking into it, it looks as if the new sensor attached to that window is in zone 1 too.



I have some sort of junction box beside the front door and it looks as if the phone line comes into that. But also the entry contact to the door that I think is faulty and the shock sensor going to the window. I presume this is then attached to the panel.

How does this change things? Can I just disconnect the sensors from here and check the resistance?

KoolKid

Ivan E wrote: »

How does this change things? Can I just disconnect the sensors from here and check the resistance?

You can. But ideally you still need to locate the end of line resistor & test the resistance on the complete loop. This would also check the connections going through that junction etc.

altor

Ivan E wrote: »

Sorry lads, I just copped something. I was looking at the original install notes attached to the panel. I have forgotten I had got a new window put in since. Looking into it, it looks as if the new sensor attached to that window is in zone 1 too.



I have some sort of junction box beside the front door and it looks as if the phone line comes into that. But also the entry contact to the door that I think is faulty and the shock sensor going to the window. I presume this is then attached to the panel.

How does this change things? Can I just disconnect the sensors from here and check the resistance?

You would need to test the loop as a whole as apposed to just checking the individual devices. A bad connection or a problem with the cable would also cause the false alarms.

Ivan E

Just to update on this, I did find the end of loop resistor on the other shock sensor I had forgotten about. I tried measuring the resistance at that junction box but wasn't really getting anything and left it on the long finger.

I got back to it today. I removed the end of line resistor on the shock. I then removed the wires on the panel and connected them to the multimetre. Thinking about it now, I may not have removed the resistor probably as there are three connection points on the shocl sensor. One wire went into the first, the second was attached to a resistor going into the second and the third had the other end of the resistor going in. I just detached the resistor end attached to the wire and connected the wire directly in.

Anyway, the multimeter was giving me a reading of 1503 when closed. I had it set at 2000Ω as I was getting a reading at that. This would jump up by 2 or 3 but roughly stay around that. When open it went to 1842, again moving up by 2 or 3 Ω. I tried it a few times and the readings always stayed the same.

I have been disabling the contact sensor for the past few weeks and haven't had any issues.

Does this rule out the sensor itself as being the problem?

KoolKid

Possibly.
When you meter the zone out without the end of line resistor the meter should be set to 200 ohms. If at that stage something sticks up by a few ohms or more I would be replacing.

Ivan E

Sorry lads, I never came back to update this post. And now I have another question, I should really update this. As I know myself, these threads are invaluable so it's always good to have a conclusion on them. It was my lack of knowledge that lead me down the wrong tracks here but what you were both saying was right, it was a faulty sensor and I was able to track it down and replace it. It's been 12 months now and have had no further problems with that particular issue. Thanks.

KoolKid

Thanks for the update. Was happy to help.