Honeywell Dual-tech PIR rapid-flash code

[Mr Pig]

Hello,

I have installed an Accenta Mini system with LCD RKP and a Honeywell DT8016F5 Dual-Tec PIR in a large wooden shed and the PIR is giving me intermittent false alarms.

The system worked perfectly for about a month, zero false alarms. Then a false alarm three days in a row! After that, maybe one false alarm every couple of weeks.

I have checked the wiring and connections and grounded the outer braid on the cable. Eventually I realised that the PIR was going into 'fast-blink' (fault) mode and this is what's triggering the false alarms but I can't find information on what causes this fault state.

The couple of times I've caught the PIR in fast-blink mode it stays in this mode for maybe five-minutes then returns to normal and works fine.

Does anyone know what kinds of fault trigger this 'fast-blink' mode?

Thank you in advance for any advice you can offer.

 

[bernardgreen]

How cold was it when the PIR went into fast blink mode. ? Some of the bestter quality PIRs have temperature sensors to adjust the sensitvity of the PIR depending on the temperature. Fast blink / alarm may be the indication that the temperature is too cold ( or hot ) for the PIR to work properly.

 

[sparkymarka]

What's it say in the installation sheet ? Did you adjust the microwave range when you fitted the detector ?

 

[Mr Pig]

The ambient temperature is not something I'd considered. I didn't know these microwave sensors were temperature sensitive. One of the false alarms was at three in the morning but the others were all during the day. It's winter so it is cold at times but I don't remember the false alarms coinciding with particularly cold days. The shed has been iced up solid with no problems but obviously in a shed it is likely to see large temperature fluctuations. That was the main reason I chose a dual-tec as I thought it would be more tolerant and less likely to give false alarms.

The, fairly pathetic, data sheet does not give an operating temperature range. There is a pot to adjust the microwave range. When first installed I left it on full, as it seemed to work fine, and it worked like that for a month. When trying to eliminate the false alarms I turned it down as low as it would go, which is five-meters, but I still got false alarms. I couldn't leave it set to five-meters because that doesn't cover the shed which is 24-feet long.

Thanks for the input. I'm going to see if I can find data on the operating temperature of this PIR. Would a different type of sensor be better for a shed?

 

[secureiam]

Don't really know your shed however.

1. Direct sunlight/ light wont help (false alarm at 3am isn't sunlight)
2.Microwave should be adjusted for range, given microwave go through brick walls a shed wouldn't be a major issue.
The instructions should recommend adjustment so the microwave stays within the shed.
3.Is the detector suffering form any condensation
4.The temperature range of the detector is usually stated on the instructions(-10 to +55oC according to data sheet I just looked at).
5.Any signs of cobwebs?

 

[Europlex]

From experience MWDs should be installed and powered up on their minimum range setting, then after a short period to 'warm up' and settle down, no one in the room, (have a cup of tea) then adj very gently until the required cover is gained.
You'll be surprised at how easy it is to get good cover with little range.

As a guide, if you stand at the furthest point possible from the detector and wave your arms about the alarm should not operate, best would being able to walk 3 paces before activation, much less chance of a false activation, any intruder is going to move about more than that.

 

[Mr Pig]

Thank you for the input.

To my knowledge the temperature in the shed has not been below -10 and certainly would not have been during most of the false alarms. There are no cobwebs and condensation is unlikely.

I had not thought about the microwaves passing through the shed. It would be impossible to prevent that. The range of the microwave detector is dialled back so that it covers the far end of the shed and no more, which is what I need it to do.

I do not think the issue is the microwave detector picking up movement outside the shed. Apart from the fact that where shed it sited there is unlikely to be any, it's a dual-tec so need both the MW and PIR to trip simultaneously to trigger an alarm. Under test that has been the case, you can't get an alarm with just one sensor.

Like I said in the first post, the sensor is going into 'rapid-flash' mode, which is a fault state. What I do not know is what kinds of fault can cause it to to this. Is it a power fault, a fault in the sensor itself, I have no idea and I can't find information on it.

 

[sparkymarka]

What's in the shed ?

 

[Handymanjo]

Is the sensor pointing at large amounts of metal ? Could be microwave turned up too high and microwave bouncing back of metal .Has that model of Dualtec got anti masking function ?

 

[Mr Pig]

What's in the shed ?

Mostly space. There is a seating area at one end, work space in the middle and the far end will store bikes. So you've got a large bench, wooden rack with tools and sundries, pictures and signs on the walls.

I don't know if it has anti-marking. There are metal objects in the shed, a bike stand being the largest at the moment as there are no bikes in the shed yet. Could reflection of the microwaves cause a fault state (rapid-flash)?

One of the times my son and I were trying to figure out what was going on the sensor went into rapid-flash while we were walk-testing it. The sensor stayed open circuit until after a few minutes the rapid-flash stopped and the sensor behaved normally again.

The rapid-flash state surely only indicates a set number of possible faults? How can I find out what they are?

 

[sparkymarka]

Sounds like a power issue to me .... Have you checked the voltage at the detector ?

 

[Handymanjo]

If you are still having issues I would change the sensor for another. Try Texecom DT or Optex DT or if you have another Honeywell one on different zone you could swop unit and see if same fault occurs ?

 

[Mr Pig]

Sounds like a power issue to me .... Have you checked the voltage at the detector ?

No, I'll try that. I don't have another detector to try, the other zones are magnetic latches. Are the Texecom and Optex sensors better? We've got dual-tec sensors in the factory at work and they've never given a false alarm in years of service.

 

[Mr Pig]

I checked the voltage and it was 13.7v. I also dialled back the microwave sensitivity a bit more so it's picking up at he far end of the shed and no more.

Before doing that I got my son to walk around the outside of the shed to see if the microwave sensor saw him and it didn't.

 

[Mr Pig]

Switch the Dual-tec back on last night and bingo, another false alarm today. That's with the microwave sensitivity turned almost fully down.

I take it no one knows what the fast-blink code means?