Siemens SITRANS FX300, Руководство по эксплуатации, Страница: 33 / 80

ELECTRICAL CONNECTIONS
4
33
SITRANS FX300
www.siemens.com/flow 06/2009 - SFIDK.PS.050.F2.02 A5E02100423
4.3 Electrical connection of current and pulse output
• Current output: Current output: Current output: Current output:
In some cases, a shielded or twisted cable may be necessary. The cable shield may only be
earthed (grounded) at one place (on the power supply unit).
• Pulse output: Pulse output: Pulse output: Pulse output:
When using the pulse output, two separate signal circuits are necessary if the pulse output is
utilized together with analogue signals. Each signal circuit requires its own power supply.
The total resistance must be adapted so that the total current I
tot
does not exceed 100 mA.
• Connection current output on terminals A, A+
Connection pulse output on terminals B, B+
The maximum load resistance is calculated as follows:
Figure 4-2: Electrical connection of current and pulse output
1 Power supply per signal circuit
2 Optional display unit
3 Load for HART
®
≥
250
Ω
4 e.g. counter
MA_Siemens_Sitrans_FX300_R02_en_PRT.book Page 33 Monday, June 22, 2009 8:17 AM