LDM59DIM LHDC MONITOR The module is designed to monitor a length of Digital Linear Heat Detecting Cable (LHDC) for both Fire condition, and Fault status (open circuit). Digital LHDC may be employed in lengths up to 5Km. Signalling of fire and fault status by means of volt free contacts. The units has open collector type solid state outputs for local indicators. The DIN rail modular form of the unit enables it to both be provided in a variety of discrete housings and readily integrated into multi zone control panels. The primary features of the control units are: LHDC Hazardous rea use by means of Intrinsically Safe Zener arrier. Fault monitoring of LHDC for open circuit conditions. LED indication of Fire, Fault & Supply status. Integral Test & pushbuttons. Volt free contact outputs for Fire & Fault conditions. Indicator and control switch connections for local fascia implementation DIN Rail mounting. LDM59DIM Data Sheet D55 Issue 6 May 0 Page of 5
LDM59DIM LHDC MONITOR Principles The unit is operated in conjunction with a length of Digital Line Heat Detector Cable (LHDC) and an end of line () terminator. The LHDC is a twisted pair twin core cable. When the trigger temperature of the LHDC is reached these cores connect and a Fire larm is registered. The LDM59DIM module monitors the LHDC. Reference should be made to the (separate) data sheet on the Line Heat Detectors for specification of their performance. There are three principle modes of supply & signalling operation : Figure shows a typical system where the LHDC is connected via a junction box & interposing cable. The repeat contacts may be employed to signal an alarm panel and/or initiate control systems. LINE HET DETECTOR TERMINTOR FIGURE J INTERPOSING CLE LDM59DIM REPET CONTCTS ( Sets) REPET CONTCTS Vdc Figure shows an arrangement for a Hazardous rea employing an intrinsically safe zener barrier. LINE HET DETECTOR J IS RRIER LDM59DIM REPET SIGNLS FIGURE HZRDOUS RE SFE RE Vdc Module rrangement 7 58 5 6 7 8 9 0 LEDs 90 PTOL LDM59DIM RESET Pushuttons 5 6 7 8 9 0 FIGURE DIN Rail 5mm Symmetrical LDM59DIM Data Sheet D55 Issue 6 May 0 Page of 5
LDM59DIM LHDC MONITOR Enclosures The unit can be mounted in a variety of enclosures including multi zone alarm panels and Explosion Proof cases. The example shown combines two zones of detection and incorporates a DIN rail mounting power supply. The case is flame resistant polystyrene, colour RL 705. Ingress protection rating is IP65. 00 00 86 86 SUP PLY SUP PLY DC LO DC ON PTOL LDM59DIM RES ET PTOL LDM59DIM RES ET Operational Specification Hinged Transparent Door 0 Vac / Vdc PSU Supply Voltage: 0 Vdc Supply Current: <**m Normal / Fault <**m larm / Fire LHDC Terminator: K End Of Line resistor. Indicators: larm : Red off Fault: Yellow off Supply: Green off Pushbuttons: larm Test Fault Test / Relay Contacts: larm changeover sets (0.5 @ 0 Vdc) Fault changeover set Lamp outputs: (O/C type) Remote Inputs: larm switch to 0V 00m Fault switch to 0V 00m Lamp Test FIGURE Connections Typical 0 Vdc 500 m FIGURE 5 K DIGITL LINE HET DETECTOR CLE 5 6 7 8 9 0 LHDC NO NC COM NO NC COM COM NC NO Remote / Fascia Indicators larm larm Fault Relay Normally DeEnergised Norm. Energised LDM59DIM DIGITL INTERFCE MODULE Flt Flt Tests Remote Indicators Remote/ Common 0V Supply V ++ Remote s s 5 6 7 8 9 0 Power Supply 0 Vdc + LDM59DIM Data Sheet D55 Issue 6 May 0 Page of 5
LDM59DIM LHDC MONITOR Hazardous reas IS arriers The LHDC may be installed in a Hazardous rea by employing an Intrinsically Safe Zener arrier which ensures that even under fault conditions the LHDC circuit has insufficient electrical energy to produce a spark initiated explosion. oth arrier and LDM59DIM module must be located in a Safe rea or Explosion Proof enclosure. Each arrier type specifies maximum parameters for cable located in the Hazardous rea. These parameters are: Capacitance (C), Inductance (L) & Inductance to Resistance Ratio (L/R). The whole of the hazardous area circuit, both LHDC and interposing cable, must comply in all three aspects. For use with the LDM59DIM Patol recommends a Dual Channel Shunt Diode C arrier, 5V 50m R per channel. MTL 7765 by Measurement Technologies Ltd. is of this type. The CLL/R parameters for the barrier depend on the configuration and gas group. When considered together with the LHDC & interposing cable specification they will determine the compliance of an installation and/or define maximum cable lengths. COMINED CHNNEL CONFIGURTION Whilst the supply 0V must be maintained within V of earth, by employing both channels of the barrier (Figures 7 & 8) the circuit is isolated from earth at the IS arrier, thus obviating multiple earth points on Fire Panel signalling systems such as addressable loops. HZRDOUS RE SFE RE IS RRIER C L L/R to be considered for arrier / Gas Group (MTL7765) Linear Heat Detector Cable CH CH INTERFCE / LDM59DDL FIRE PNEL Trigger 0 Circuit 9 + _ C + C = C to be considered for arrier / Gas Group L + L = L to be considered for arrier / Gas Group IS ERTH Greater of L/R L/R to be considered for arrier / Gas Group C L L/R C L L/R JUNCTION IS RRIER OX (MTL7765) Linear Heat Detector Interposing CH CH FIGURE 6 INTERFCE / LDM59DDL FIRE PNEL Trigger 0 + Circuit 9 _ IS ERTH FIGURE 7 EXMPLE : The parameters for the MTL7765 in a combined channel configuration (Figs 6 & 7) for a group IIC gas are : Maximum Capacitance C=0.58uF Maximum Inductance L=0.mH Maximum Inductance to Resistance Ratio L/R=uH/ohm. Patol 70deg. Nonrmoured LHDC has C=0pF/m, L=0.95uH/m, L/R=5.5uH/ohm. With no interposing cable the predominating factor in this case is inductance which limits the LHDC length to 6m (0. / 0.00095). SINGLE CHNNEL CONFIGURTION nother arrangement is a single channel circuit which permits greater lengths of LHDC to be installed. HZRDOUS RE SFE RE IS RRIER C L L/R to be considered for arrier / Gas Group (MTL775) Linear Heat Detector Cable CH CH LDM59DIM Supply 0 Circuit 9 POWER + _ Vdc FIGURE 9 LDM59DIM Data Sheet D55 Issue 6 May 0 Page of 5
LDM59DIM LHDC MONITOR The configuration of fig.8 shows one side of the LHDC circuit returned to earth. EXMPLE : The max parameters for the MTL775 for a group IIC gas are : Maximum Capacitance C=0.58uF Maximum Inductance L=.5mH Maximum Inductance to Resistance Ratio L/R=66uH/ohm. Patol 70deg. Nonrmoured LHDC has C=0pF/m, L=0.95uH/m, L/R=5.5uH/ohm. With no interposing cable the predominating factor in this case is inductance which limits the LHDC length to 56m (.5 / 0.00095). For further information including the full range of Patol Linear Detector CLL/R specifications refer: D0 PPLICTION NOTE LINER HET DETECTION CLE The use of LHDC in Hazardous reas by means of Intrinsically Safe arriers The above information is a guidance note. National / Local Regulations, Standards and arrier Specifications MUST take precedence in any system design and implementation. Operation NORML RESET LMP LHDC & Supply Voltage Normal Green Supply LED larm & Fault LEDs Off larm & Fault Indicator outputs Off & larm relays Deenergised Fault relay Energised (Not Fault / OK output On) LHDC open circuit Yellow Fault LED On Fault Indicator output On (Not Fault / OK output Off) Fault relay Deenergised The unit will automatically return to Normal on rectification of the Fault condition. LHDC ctivated (S/C due to Fire) Red larm LEDs On larm Indicator outputs & On larm relays & & Energised Module Fire Test pushbutton operated LEDs, fire relays and indicator outputs as for Fire above. Module Fault Test & pushbutton operated OR input activated. The unit is normalised after a Fire Test pushbutton operation. n LHDC Fault condition is simulated during P operation fter a true Fire operated LHDC requires replacement before. Remote Lamp Test input activated larm & Fault Indicator outputs On Rectory Road, Padworth Common, erkshire, United Kingdom. RG7 JD Tel: + (0) 8 97070 email : info@patol.co.uk Fax: + (0) 8 970700 Web: www.patol.co.uk LDM59DIM Data Sheet D55 Issue 6 May 0 Page 5 of 5