Vega VEGAPULS 63 Operating Instructions Manual

Also see for VEGAPULS 63: Safety manual Quick setup guide Operating instructions Operating instructions Operating instructions

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Vega VEGAPULS 63 Operating Instructions Manual Manual pdf 19 page image

195 Connecting to power supplyVEGAPULS 63 • Foundation Fieldbus28451-EN-1701195 Connecting to power supply5.1 Preparing the connectionAlways keep in mind the following safety instructions:Warning:Connect only in the complete absence of line voltage.• The electrical connection must only be carried out by trainedpersonnel authorised by the plant operator.• If overvoltage surges are expected, overvoltage arresters shouldbe installed.The instrument requires a operating voltage of 9 … 32 V DC. Operat-ing voltage and the digital bus signal are carried on the same two-wireconnection cable. Power is supplied via the H1 power supply.Connection is carried out with screened cable according to Fieldbusspecification.Use cable with round cross section for instruments with housing andcable gland. To ensure the seal effect of the cable gland (IP protectionrating), find out which cable outer diameter the cable gland is suitablefor.Use a cable gland fitting the cable diameter.Make sure that the entire installation is carried out according to theFieldbus specification. In particular, make sure that the bus is termi-nated with suitable terminating resistors.Caution:No grease should be used when screwing the NPT cable gland orsteel tube into the threaded insert. Standard grease can containadditives that corrode the connection between threaded insert andhousing. This would influence the stability of the connection and thetightness of the housing.In systems with potential equalisation, connect the cable screendirectly to ground potential at the power supply unit, in the connectionbox and at the sensor. The screen in the sensor must be connecteddirectly to the internal ground terminal. The ground terminal outsideon the housing must be connected to the potential equalisation (lowimpedance).In systems without potential equalisation, connect the cable screendirectly to ground potential at the power supply unit and at the sensor.In the connection box or T-distributor, the screen of the short stub tothe sensor must not be connected to ground potential or to anothercable screen. The cable screens to the power supply unit and to thenext distributor must be connected to each other and also connectedto ground potential via a ceramic capacitor (e.g. 1 nF, 1500 V). Thelow frequency potential equalisation currents are thus suppressed,but the protective effect against high frequency interference signalsremains.Safety instructionsVoltage supplyConnection cableCable screening andgrounding