User Manual

Fibre Optic Master and Remote Site
User Handbook
Document Number: 60-212701HBK - Issue No. 1 Page 38 of 50
4.2.4.17. 12V Relay Assembly (80-008901)
The General Purpose Relay Board allows the inversion of signals and the isolation of circuits. It is
equipped with a single dual pole change-over relay RL1, with completely isolated wiring, accessed
via a 15 way in-line connector. The relay is provided with polarity protection diodes and diodes for
suppressing the transients caused by "flywheel effect" which can destroy switching transistors or
induce spikes on neighbouring circuits. Its common use is to amalgamate all the alarm signals into
one, volts-free relay contact pair for the main alarm system.
80-008901 Specification
PARAMETER SPECIFICATION
Operating voltage 8 to 30V (floating earth)
Alarm threshold Vcc - 1.20 volt +15%
Alarm output relay contacts
Max. switch current 1.0Amp
Max. switch volts 120Vdc/60VA
Max. switch power 24W/60VA
Min. switch load 10.0µA/10.0mV
Relay isolation 1.5kV
Mechanical life >2x10
7
operations
Relay approval BT type 56
Connector details Screw terminals
operational -10°C to +60°C Temperature
range
storage -20°C to +70°C
4.2.4.18. 60A Dual Diode (94-100004)
The purpose of these dual diode assemblies is to allow two DC voltage sources to be combined, so
that the main DC rail within the equipment can be sourced from either a mains driven PSU, or
externally through an XLR connector or from dual mains driven PSUs . They are very heavy-duty
diodes and they prevent any reverse current from flowing back to their source or the alternative
supply rail. Combining diodes such as these will also be used if the equipment is to be powered from
external back-up batteries.
4.2.4.19. PSU 600W (24V 23A) (96-300067)
The power supply unit is a switched-mode type capable of supplying 24V DC at 23.0Amps
continuously. Equipment of this type typically requires approximately 10.0 Amps at 24V DC, so the
PSU will be used conservatively ensuring a long operational lifetime.
No routine maintenance of the PSU is required. If a fault is suspected, then the output voltage from
the power supply may be measured on its output terminals. This is typically set to 24.5V using the
multi-turn potentiometer mounted close to the DC output studs on the PSU PCB. All the PSUs used in
AFL Cell Enhancers are capable of operation from either 110 or 220V nominal AC supplies. The line
voltage is sensed automatically, so no adjustment or link setting is needed by the operator.
96-300067 Specification
AC Input Supply
110 or 220V nominal
Voltages:
90 to 132 or 180 to 264V (absolute limits)
Frequency: 47 to 63Hz
DC Output Supply:
24V DC (nominal)
Voltage:
20 to 28V (absolute limits)
Maximum current: 23A