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Frequently asked questions

What is the difference between linear heat detection and linear heat detection cable?

None whatsoever. Heat sensing cable and linear heat detection refer to the same range of products.

What is the difference between analogue and fixed temperature cable?

There is a big difference between these two types of cable. The biggest difference being that analogue cable is resettable while fixed temperature is not. Fixed temperature cable does exactly as the name suggests, it raises an alarm at a fixed temperature. Whereas analogue cable is a rate or rise cable and will go into alarm if it detects a sudden increase in temperature. Signaline HD must be used with the associated controller. Signaline FT does not need a controller.

Does Signaline FT need a controller?

No, Signaline FT and FT-R cables do not need their own dedicated controller. Signaline FT & FT-R can be connected to a conventional fire control panel via a Signaline UCB (Universal Connector Box).

Signaline FT & FT-R can also be connected to an addressable fire control panel without a controller. Simply connect the cable to an zone monitor unit such as an Apollo ZMU (part number 55000-845APO) and place an end of line supplied by or recommended by the Zone monitor unit manufacturer at the other end.

Can I join lengths of Signaline HD to Signaline FT?

Signaline HD is a rate of rise cable. Signaline FT is a fixed temperature cable. These two cables are not compatible and therefore cannot be joined together.

What should the difference between ambient and alarm temperature?

The cables are designed to stay in an environment 20°C below the alarm temperature. This allows the ambient to fluctuate naturally, summer highs and winter lows for example, without causing false alarms. Therefore always allow at least a 20°C difference between ambient and alarm.

Where should I use the nylon coated cable?

Signaline’s nylon coating gives increased chemical and UV protection to the cable. Therefore if there are harmful atmospheric gases or long exposures to UV rays you should consider the nylon coating for your cable.

Where should I use Signaline Stainless steel braided?

The stainless steel braid is designed to protect the cable from mechanical hazards. Therefore if the cable is going into machinery such as escalators or conveyors this would be the cable you should use.

How much Signaline FT cable can you have per zone?

To comply with EN54 the maximum length is 300m. However, Signaline FT is capable of going into alarm at any point up to 3,000m. The Alarm Point Distance Locator will give you a pinpoint reading as to where the cable has gone into alarm. This is particularly useful for long tunnel applications.

Can I use Fixed Temperature on addressable systems?

Yes, very easily. Simply connect the cable to a zone monitor unit such as and Apollo ZMU part no 55000-845APO and place an end of line supplied by or recommended by the Zone monitor unit manufacturer at the other end.

Can I join lengths of different temperature Signaline FT together?

You should never join different Signaline FT temperatures together. If a different area needs a different alarm temperature you should start a new zone and use the applicable cable.

Can I use Signaline FT on systems without monitoring resistors?

Only when using Signaline FT and FT-R cables but remember you will have no monitoring of the system and system faults will not be detected.

Can I reuse a length of Signaline FT that has gone into alarm?

No, the length of cable affected must be replaced.

Can I splice a section of cable that has been damaged? What do I need to be able to do this?

Simply remove the damaged section and replace it with a new length of identical Signaline cable. Join the cable together using a Signaline junction box.

Does the Alarm Point Locator work with Analogue Heat Sensing Cable?

No it only works on Signaline FT and FT-R cable. It will pin point an alarm anywhere along a 3000m length of Signaline FT.

What’s the maximum cable length of Signaline HD per controller?

To comply with EN54 the maximum length is 300m, but any of the Signaline HD controllers are capable of monitoring up to 500m of cable.

What’s the minimum cable length of Signaline HD per controller?

The minimum amount of cable per controller is 1 metre.

What’s the difference between an SKM-03 and SKM-03UK Controller? Can I only use the latter if I’m in the UK?

The SKM-03 is fully approved by VdS Germany as an EN54 Pt5 heat detector and can be used in UK and the world over. Our SKM-03 UK controller has a modified response such that alarm is generated when 1 metre of cable is heated to 60°C. This modified response does not comply with EN54 and therefore cannot be certified by VdS. You can use this controller in any country, subject to its acceptance by the local fire services dept or other relevant body.

Can I join lengths of Signaline HD cable together?

Yes. Use a Signaline UCB (Universal Connectior Box). You can also intersperse sections of Signaline HD with basic cable to take you past areas you may not want to protect. Please ask our offices for details.

Can I reuse a length of Signaline HD that has gone into alarm?

Yes, providing it has not been destroyed. Superficial burn marks on the outer cover of the cable will not prevent the cable being reused. Please note that we cannot under any circumstances guarantee that the performance of Signaline HD that has suffered a fire will not be impaired.

Is Signaline HD fireproof?

No, it is not a fire proof cable and can be destroyed in a fire. It is a linear heat detection cable, when the heat is removed it can be reset.

Which Clip should I use?

The answer to this question depends on which cable you are using and the application you are using it for. LGM offers a wide range of clips so we will always be able to match the correct clip to your application. Please contact our offices for advice on which clip to use.

Can I use more than one type of clip on one length of cable?

Yes. The fixing clips are there simply to hold the cable in place. Use a clip suitable for whatever you are trying to fix the cable to.