Memmert INCO 246/246 med CO2 Incubators (Generation 2003) - Manual (Page 60)

60
Advanced functions
7.7.2 Bus interface RS 485
If requested on the corresponding order, the oven can be fitted in the factory with a RS-485
interface instead of a RS-232-C interface. This enables the networking of several ovens (up to
16) with one computer via a shared two-wire cable ( Fig. 34 ). The chamber must be given a
unique device address in the SETUP submenu, menu item ADdRESS (see page 46 ), via which the
computer communicates with the oven. A maximum of 16 devices can be addressed on the
RS-485 bus.
The default setting is ADDRess 0. Using this, the appropriate incubator
can be selected and programmed from the PC.
The computer needs to be equipped with either an RS-485 interface
or with an RS 232/RS 485 converter ( Fig. 34 ). Connecting the wires
is done individually with a shielded cable, depending on the installa-
tion site. The maximum total cable length is 150 m.
220 ohm terminating resistor must be connected to the last device.
Pin allocation:
1 2 3 4 5 6 7 8 9
not oc-
cupied
not oc-
cupied
A not oc-
cupied
not oc-
cupied
not oc-
cupied
not oc-
cupied
B not oc-
cupied
RS232
RS485
Interface converter
Fig. 34 Connecting incubators via the RS485 bus interface
RS 485
9-pin serial port
1 2 3 4 5
6 9 8 7
Fig. 33 RS-485
interface