Cooper TP Workshop Manual_Scant:Layout 1 7/8 ... - Cooper Security

95EN, 85EN, 65EN1. Make sure that no two devices on the same network have the sameaddress.2. Check the voltage across the A (+) and B (-) terminals; the voltage shouldbe at least 10.5V (recommended 12V). If the voltage is low, follow thesuggestions described on pages 22 to 23. If an external power supply isused, follow the advice given on page 23.3. Check for an earth fault: Switch on the mains supply and measure the DCvoltage between the mains earth connection and the AUX +12V terminal.Caution: Do not make contact with mains live or neutral! Thenmeasure the DC voltage between the mains earth connection and 0V. Inboth cases, the measurement should be 1V or less. If the voltage isgreater than 1V, the system has an "Earth Fault" and all cables should bechecked for isolation to earth. You can do this by disconnecting cablesfrom the control unit one at a time and re-measuring the voltage until thefault is located.4. Make sure that the cables are properly segregated. All network and zonewiring must be segregated from any other wiring, such as mains supplycables, telephone cables, computer network cables and R.F. cables. It isrecommended that cable ties are used to keep cables separated.The network and detection cables should be kept clear of cablessupplying sounders or extension loudspeakers. It is also advisable toavoid running more than one network down a single cable.5. Check for AC induced currents: Set the meter set to measure low ACvoltages and measure the voltage between the mains earth connectionand the AUX +12V terminal, then between the mains earth connectionand 0V. The measurement should be less than 8Vac in both cases. If thereading is greater than this, try to locate the source of the interference(e.g. radio transmitters or electrical machinery). If the reading is between8 and 10Vac, installing an Induced AC/Spike Suppression filter shouldhelp to reduce the effect.If it is necessary to use screened cable, refer to the advice given under theheading "General Wiring Considerations" in the 95EN InstallationInstructions.6. Check that cables do not exceed the maximum specified distances givenon page 18. A Networker Interface Board (NIB) can be used to increasecable distances (see page 19).7. Make sure that no more than 4 devices are star connected to an MSNodeor control unit (see page 18).69 of 72