Interfaces
42
130000761_002_A0 - 08/2008 - © Oerlikon Leybold Vacuum
3.3.2 RS 485 interface
Standards
ISO/IEC 8482, EIA 485
Protocol
acc. to VDI/VDE 3689
Transmission rate
19200 baud fixed
Response delay
default setting 10 ms
(parameter 180)
Address range
0 ... 15
Max. cable length
50 m (with bus termination)
Type of cable
2 wire twisted pair
(twisted pair cable)
Differential voltage levels
logic "0":
(see also “Standards”)
transmitter: 1.5 ... 5 V
receiver: > 0.3 V
logic "1":
transmitter: - 1,5 ... - 5 V
receiver:
≤
- 0,3 V
Interface connector
9 way Sub-D type,
socket on the instrument (male)
thread UNC4-40
Note: After having changed the bus address through the rotary switch , the
frequency converter must be switched off (yellow power LED off) and then on
again so as to enable the new address setting.
Bus addresses over 15 can only be set via Parameter 37.
Refer also to Operating Instructions GA 05.281
7
8
9
1
2
3
4
5
6
TxD/RxD +
TxD/RxD –
0,5 A, 24 V DC
Fig. 3.3 Pin assignment for the socket at the frequency converter for RS 485 interface (male)
Links for activation of
the bus terminator
