Yokogawa RAMC - Manual (Page 50)

<7. HART-COMMUNICATION>
7-2
IM 01R01B02-00E-E 10th edition January 01, 2013 -00 All Rights Reserved. Copyright © 2003, Rota Yokogawa
7.2 Connection
The connection is carried out in accordance with below figure. Please note, that the load resistor must have a
value between 250 and 500Ω .
The minimum power supply is 13.5V + (RL*20mA) ; RL = load resistor
The maximum power supply is 30V.
As connection cable a protected twisted cable pair is recommended.
15
4 6 3 1
14
12 10 11 8 7 9
U
F
G
RAMC
A
Power supply
U
Mains 230V AC
KFA6-SR2-Ex2.W
Option: /W2B Transmitter Relay
Limit MI
N
Limit MAX
Option / KnE
Rotameter
4-20mA
Max Min
12 11 10 9
Limit switches EN 60947-5-6 (Namur)
One channel connection like
limit MAX
4-20mA
RL
HART-Communication
with HART-Communicatio
n
without HART-Communication
Power supply U/V
RL/Ohm
13,5V+(RL*20mA) ...
30V
13,5V ...30V
< (U-13,5V) / 20mA 250 ... 500 Ohm
- +
- +
- + - +
~
~
+ - + -
F71.EPS