LB 134
2. System Description
21
2.4 Data Interface
The LB 134 has two USB ports, a USB host and a USB device
interface with the appropriate connectors. However, both can-
not be used simultaneously. A memory stick can be connected
to the USB host interface, and a PC to the device interface. Pa-
rameters can be uploaded and downloaded, currently meas-
ured data or the entire memory contents can be transferred to
PC and various measurement functions can be executed using
a PC program. The program creates different graphics and ar-
chives measured data or parameter files. The complete meas-
urement data memory can be transferred or parameters can be
uploaded to and downloaded from the memory stick.
Furthermore, an RS485 interface is available, allowing integra-
tion of the device into a local network. Up to 32 measuring de-
vices including central computer can be integrated in this net-
work with a cable length of up to 1000 m. The baud rate to be
set depends on the cable length and the number of connected
devices. The standard cable used is a shielded twisted pair da-
ta cable which has to be terminated at each end of the bus be-
tween both wires with 120 ohms. The cable shielding is con-
nected to ground at the central station of the network. The
shielding may also be connected to device ground at the indi-
vidual measuring stations with LB 134, as long as they are op-
erated with the power supply units provided, as these do not
have any connection to the local ground (no protective earth
connection) and thus cannot produce any undesirable ground
potential differences.
The F²C protocol, which is also implemented in some other BT
devices, is used for serial data communication via USB or the
RS485 interface.
The baud rate for the USB interface is always constant at
38,400 baud and cannot be changed; for the RS485 interface it
can be selected between 2,400 and 38,400 baud. (Menu Pa-
rameter/Hardware). The other parameters are fixed: data bits:
8; parity: none; start bit: 1, stop bit 1, no handshake.
At the end of each cycle, if selected, the following data is written
to a memory (read-only memory or FIFO):
Содержание LB 134
Страница 1: ...LB 134 Universal Monitor II Program version V 1 00 and higher ID No 62688BA2 Rev No 02 08 04 2016...
Страница 2: ......
Страница 6: ...LB 134 Content IV...
Страница 8: ...LB 134 Working with the User s Manual VI...
Страница 10: ...LB 134 Safety Instructions VIII...
Страница 34: ...LB 134 2 System Description 24 Figure 2 9 LB 134 with wall bracket...
