Mpi with isolated rs485, Comms cables for port 2, Comms cables for port 1 – Innotech Genesis V4 System User Manual
Page 108: Mpi with non-isolated rs485, Measurements made with earth wire connected
Installation Instructions for Innotech Genesis Systems
Edition 011100
A-27
Figure A-26. Voltage Check, GENII MPI with Isolated/Non-Isolated RS485.
Figure A-27. Voltage Check, GENII RPTR Repeater Module.
Measure all voltages to the metal shell of a DB connector on the MPI with the MPI
connected to a PC or Printer which is plugged into a standard power point (outlet).
MODEM
PC
PRINTER
V
AC
V
DC
3.5
MPI With Non-Isolated RS485
MODEM
PC
PRINTER
V
AC
V
DC
24V
MPI With Isolated RS485
Measure AC and DC
voltages: Should be
less than 3.5Vac and
between +10Vdc and
-5Vdc.
Measure AC and DC
voltages: Should be
less than 24Vac and
between +33Vdc and
-33Vdc.
Comms Cables for Port 2
V
AC
V
DC
24V
1
2
Isolated from
internal circuit
Connected to
internal circuit
EA
R
TH
L
N
E
Measurements Made
With Earth Wire
Connected
Comms Cables for Port 1
V
AC
V
DC
3.5V
1
2
Isolated from
internal circuit
Connected to
internal circuit
EA
R
TH
L
N
E
Measure AC and DC
voltages: Should be
less than 3.5Vac and
between +10Vdc and
-5Vdc.
Measure AC and DC
voltages: Should be
less than 24Vac and
between +33Vdc and
-33Vdc.