Super Systems 9205 Series - Manual (Page 7)

Series 9205 Operations Manual Rev A 6
Wiring
It is important to connect the controller in accordance with the wiring data given in this handbook.
Take particular care not to connect AC supplies to the low voltage power supply input. Use copper
wires for 24V DC power supply to the instrument. Ensure that the wiring of installations comply
with all local wiring regulations. For example in the United Kingdom use the latest version of the
IEE wiring regulations, (BS7671). In the USA use NEC Class 1 wiring methods.
Power Isolation
The installation must include a power isolating switch or circuit breaker. This device should be in
close proximity to the controller, within easy reach of the operator and marked as the
disconnecting device for the instrument.
Earth leakage current
Due to RFI Filtering there is an earth leakage current of less than 0.5mA. This may affect the
design of an installation of multiple controllers protected by Residual Current Device, (RCD) or
Ground Fault Detector, (GFD) type circuit breakers.
Over current protection
To protect the internal PCB tracking within the controller against excess currents, the AC power
supply to the controller and power outputs must be wired through a fuse or circuit breaker
specified in the technical specification.
Voltage rating
The maximum continuous voltage applied between any of the following terminals must not
exceed 24V DC
• relay or triac output to logic, DC or sensor connections;
• any connection to ground.
The controller should not be wired to VAC. The 24V DC power supply voltage across the
connections and between the power supply and ground must not exceed 2.5kV. Where occasional
voltage over 2.5kV are expected or measured, the power installation to both the instrument
supply and load circuits should include a transient limiting device.
These units will typically include gas discharge tubes and metal oxide varistors that limit and
control voltage transients on the supply line due to lightning strikes or inductive load switching.
Devices are available in a range of energy ratings and should be selected to suit conditions at the
installation.