Omron VARISPEED E7 User Manual page 57

* 3. When driving a reactive load, such as a relay coil with DC power supply, always insert a flywheel diode as shown in
2
Switch S1 - Standard Terminal Board
The Switch S1 can be used to terminate the internal RS422/485 port and for selecting the input signal type for
analog input A1. See
The settings of switch S1 is shown in the following table.
Name
S1-1
S1-2
Switch S1 and Jumper CN15 - Optional Terminal Board
An optional terminal board which supports switching the signal type of the analog outputs FM and AM
between voltage and current is available.The switch over can be performed using jumper CN15. The switch
S1 has the same function like on the standard terminal board. See
22
2-
Coil
External power:
30 VDC max.
Fig 2.11 Flywheel Diode Connection
Fig 2.12 for details.
S1
RS422/485 Port Termination Resistance
Off On
Analog Input A2 Current/Voltage Signal Selection
V I
Fig 2.12 Standard terminal board - Switch S1 function
Function
RS-485 and RS-422 terminating resis-
tance
Input method for analog input A2
CN15
Analog Output FM Current/Voltage Signal Selection
Ch1
Ch2
Analog Output AM Current/Voltage Signal Selection
I V
S1
RS422/485 Port Termination Resistance
Off On
Analog Input A2 Current/Voltage Signal Selection
V I
Fig 2.13 Optional terminal board - Switch S1 and jumper CN15 function
Flywheel diode
1 A max.
OFF: No terminating resistance
ON: Terminating resistance of 110 Ω
V: 0 to 10 V (internal resistance: 20 kΩ)
I: 4 to 20 mA (internal resistance: 250 Ω)
Fig 2.13
Fig 2.11
.
The rating of the flywheel diode
must be at least as high as the cir-
cuit voltage.
Setting
for details.