2.5 Noise considerations
All motor starters, contactors or any other inductive or noise generating devices should be mounted in either a
separate control panel or in a separate section of the RBPC enclosure, at least 305 mm (12”) away.
When the RBPC is mounted in an enclosure or a control panel, use separate conduit entrances for low voltage
wiring and 120 V AC wiring.
2.6 Understanding the fault messages (what to do?)
The faults in the RBPC are generated one at a time. If a fault occurs, the fault has to be corrected first and then it
has to be reset on the main screen. The faults are generated and stored like a deck of cards, one on top of another.
If multiple faults have occurred then once the first fault is cleared the next one will appear instantly after the first. All
errors are saved in memory. If a power down occurs those same faults will re-appear the next time the control
powers up. Please refer to Appendix 1 in the RBPC User’s Manual for a detailed listing and explanation of all faults
messages.
2.7 PLS Outputs
In order to cover a wider range of applications with the standard configuration, the PLS outputs of the RBPC are
factory equipped with general purpose electromechanical relays. However, it is important to note that the service
life of electromechanical relays is inversely proportional to the load current and to the number of operations; that is,
the greater the number of cycles that an electromechanical relay is actuated and the higher the current through its
contacts, the shorter its service life.
This wear mechanism can be particularly significant when the PLS outputs are programmed to operate at relatively
high speeds (e.g. > 100 cycles per minute), as these operating conditions can lead to a premature failure of the
relay which, ultimately, must be replaced.
To address this problem, ISB recommends the use of optional solid-state relays, which, having no moving parts,
provide a longer lifetime and trouble free operation.
However, unlike their electromechanical counterparts, which can be used in a wider range of applications, solid-
state relays must be selected according to the specific loading conditions (AC or DC, voltage and current) of each
particular application. Please use the information in the table below to select and order optional ISB solid-state
relays:
ISB Part number
Description
22 0240 00
Solid-state relay, AC output, 1 A @ 250 V AC (black colour)
22 0242 00
Solid-state relay, DC output, 1 A @ 60 V DC (red colour)
Please also note that the load ratings of the solid-state relays is lower than the standard relays provided with the
RBPC.
⚠
WARNING: Exceeding the maximum ratings of the solid-state relays may cause permanent damage
to the device and may also lead to damage to the internal circuitry of the RBPC
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