Edition 14

Syncro Analogue Addressable Fire Control Panel

Apollo Loop Calculator – Revised Syncro panel information

The Apollo Loop Calculator application is a powerful utility to allow the design of the fire detection system to be verified prior to installation.

The program allows system engineers to add a number of variables, such as quantities of XP95 and Discovery devices, loop cable type and control panel selection. The program will advise if the system design is satisfactory or may exceed system limitations.

It has been identified that for the Syncro control panel, the calculated maximum loop cable length was significantly lower than contemporary panels from other manufacturers. Following a detailed investigation, the reason for this discrepancy was identified to be due to an incorrect loop driver impedance value in the Loop Calculator panel settings file.

The Syncro loop driver circuit impedance is less than 2.5 ohms, but a value of 20 ohms was being used in the Loop Calculator application. The resultant effect of using the higher loop driver impedance is a reduced calculated maximum loop cable length and increased calculated voltage drop.

The effect of the incorrect loop driver impedance value means that previous loop calculations will work, as it reduced the capability of the Syncro loop rather than exaggerated the loop capability. However this reduced capability may have resulted in some panel loop calculations failing, when in fact the system would possibly have worked without problems.

A patch in the form of a small self-extracting ZIP file is available for download from the Apollo web site using the link below.

Revised Apollo Loop Calculator standard panel data file:

Sigma CP
Fire Control Panel

Sigma CP – Sounder Card Expansion Capability

The Sigma CP is an approved and BSI certified conventional control panel, available with 2, 4 or 8 conventional detection zones and two conventional sounder outputs.

The “T series” Sigma CP panels also allow sounders to be fitted to the detection zones, in addition to the two standard sounder circuits. However the “T series” control panels require special detector base circuits to allow the detection devices to operate on the same two wires as the zone sounders.

In some installations, it is desirable to provide additional dedicated sounder circuits, in particular in retrofit applications and in installations where zonal or two-stage ringing patterns are required.

For intrinsically safe installations, there is a limit in the number of IS sounders that can be installed in the protected area, due to the isolating barrier current. Typically only one or two Intrinsically Safe sounders can be powered from each circuit, therefore additional circuits are often required to ensure sufficient audibility in the IS area.

The Sigma CP sounder board, Kentec part number S461, will satisfy these additional sounder circuit requirements.

The Sigma CP sounder board provides eight individually monitored sounder circuits, each rated at 500mA and protected by an electronic fuse. These 8 sounders may be configured to operate in the following patterns:

  • Common - all sounders outputs operate from a fire in any zone.
  • Zonal - only the sounder output allocated to the zone in fire will operate
  • Two-stage - the sounder allocated to the zone in fire operates continually, all other sounder outputs pulse.
Each sounder output on the S580 board has an “activated” indicator to allow easy identification of energised sounder outputs.

A local “class change” input is also provided, which will operate all 8 sounder outputs for the duration that the input is active.

The sounder board is connected to the Sigma CP using RS485 data, and therefore can be installed up to 1200m from the control panel, using suitable RS485 compatible data cable. Up to 7 sounder cards can be connected to each Sigma CP panel, providing additional sounder expansion capacity in different locations.

As the sounder card can potentially draw up to 4 Amps from the 8 sounder circuits, power consumption must be considered. In most instances the combined sounder load and board current consumption exceed the Sigma CP 500mA auxiliary power supply output.

Kentec can supply the Sounder card in a Sigma CP style enclosure and with a power supply, for installations where the unit cannot be directly powered from the Sigma CP panel.
Kentec part number K04000 M2 - Boxed Sigma CP Sounder Card, no power supply
Kentec part number K044000 M2 - Boxed Sigma CP Sounder Card PCB c/w 4A power supply

Note: The Sigma CP panel must be fitted with firmware version 2.42 or later to support this product. This is identified by the software label on the rear of the Sigma CP board, which should show “SIGMA242.HEX” or later.

For more information on the S461 sounder card:

For the latest Sigma CP manual:

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Kentec Electronics Ltd.
Tel: +44 (0)1322 222121 Fax: +44(0)1322 291794