SAMI G S 6.1 Control Cables Control cables for the SAMI GS should be 0.5 - 1.0 mm 2 screened, multi-core cables. must be protected by using varistors or RC units (AC) or a diode (DC). The protection components should be installed onto the coil of the relay or contactor being controlled and not on the terminals of X50. When using an RC unit, note that the leakage current of the RC circuit must be less than the holding current of the controlled contactor or relay. The cable screens should be earthed at the PE of the frequency converter chassis.
When planning the cabling between the SAMI GS and an automation device, such as a PLC, attention should be given to interfer- ence suppression, signal levels, galvanic isolation, etc. These cables should be separated from the mains and motor cables and not running in parallel with them (mini- mum separation 300 mm if parallel run should be no additional control components (contactors or relays) inside the SAMI GS and no control cables other than those of the SAMI GS. The control connections of the SAMI GS are galvanically isolated from mains potential and have a 10 M Ω resistance from the inverter frame i.e. PE.
Because of this, there is no need to connect X50/2,4,6 and 8 (logic GND) to TE or PE. However, it could prove useful to do this if EMC problems occur. Analogue input and output signals: A separate twisted pair must always be used for each individual signal. Digital inputs: It is strongly recommended to use screened cables for digital inputs (DI). An external +24V supply for the digital inputs (DI1 to DI6) must not be used. Relay outputs: If relay outputs (RO) operate on 24 V DC, the signals can be routed to the same cable used for the digital inputs. If twisted cables are used, digital output and input should never be in the same pair.
If 110 V/230 V AC is connected to a relay output, a separate cable without screen can be used for these signals. Note! If the relay outputs are used to control inductive loads (e.g. relays, contactors) they 20