Endress+Hauser RMS 621 - Page 60

10 Technical data RMS 621
60 Endress+Hauser
Loop power supply and
external power supply
• Transmitter power supply (TPS), terminals 81/82 or 81/83 (optional universal expansion cards
181/182 or 181/183):
Supply voltage 24 V DC ± 15%
Max. current 30 mA, short-circuit proof
HART
®
communication is not accounted for
Number 2 (in basic device)
Maximum number: 8 (depends on number and type of expansion cards)
• Additional power supply (e.g. external display), terminals 91/92:
Supply voltage 24 V DC ±5%
Max. current 80 mA, short circuit protected
1 power supply available
Source resistance< 10 Ω
10.0.3 Power supply
Supply voltage • Low voltage power unit: 90 to 250 V AC, 50/60 Hz
• Extra-low voltage power unit: 18 to 36 V DC or 20 to 28 V AC, 50/60 Hz
Power consumption 8 to 26 VA (dependent on the expansion stage)
Connection data interface
RS232
– Connection: 3.5 mm (0.138 in) jack plug on front panel
– Transmission protocol: ReadWin
®
2000
– Transmission rate: max. 57,600 Baud
RS-485
– Connection: plug-in terminals 101/102
– Transmission protocol: (serial: ReadWin
®
2000; parallel: open standard)
– Transmission rate: max. 57,600 Baud
Optional: additional RS-485 interface
– Connection: plug-in terminals 103/104
– Transmission protocol and transmission rate same as standard RS-485 interface
(Second RS-485 interface is active for as long as the RS232 jack plug is not used.)
10.0.4 Performance characteristics
Reference operating
conditions
• Power supply 230 V AC ±10%; 50 Hz ± 0.5 Hz
• Warm-up period > 30 min
• Ambient temperature 25 °C (77 °F) ± 5 K
• Humidity 39% ±10% r. F.