B&B Electronics MES1A - Manual (Page 17)

Hardware Overview
Manual Documentation Number: MES1A/MES1B-2106m PN7138-rev001
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104 – www.bb-elec.com
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445 – www.bb-
europe.com
7
Figure 6. RS-485 Two-Wire Connection
No jumpers are required to bridge the transmit and receive lines in
two-wire mode.
Power Connector
The Power Connector is a removable two-position screw terminal
block with screw down. The MES1A/B requires between 10 VDC
and 30 VDC (3.6 Watts). Typically a 12 VDC power adapter is
connected to the terminal block via bare wires. The terminal block
can be unplugged to remove the converter from service.
Figure 7. MES1A/B Power Connector
Connecting the Hardware
The MES1A is connected to its Modbus device via a DB-9M
connector and an RS-232 cable. The MES1A is configured as a
DTE. If the connected Modbus device is configured as a DCE, use a