Rigol M300 - Page 16

RIGOL
M300 Quick Guide
8
5. DMM Module Power Fuse
The AC power supply from the power socket is divided into two paths with one
for the DMM module and the other for other circuits except the DMM module.
M300 is equipped with the DMM module power fuse (its specification is AC 250V
T250 mA). To replace the fuse, refer to the method below.
1) Turn off the instrument and remove the power cord.
2) Press down the fuse cover using a straight screw driver and rotate
clockwise.
3) Disassemble the fuse cap and fuse.
4) Replace a specified fuse and install the fuse cap.
CAUTION
Please use the specified fuse to avoid electric shock and fire.
6. Voltage Selector
M300 supports two kinds of AC voltages (115 V and 230 V). Please select the
proper voltage scale according to the AC power used.
7. RS-232/Alarms/Ext Trig Mix Interface (Male)
This interface is 25-pin male interface. You can convert this interface into two
9-pin interfaces using the Mix Interface Convert Cable (accessory); wherein, one
is a 9-pin male interface used as a standard RS232 interface and the other is a
9-pin female interface used for alarm output, external trigger signal input, etc.
 RS232: via this interface, M300 can communicate with the PC and you can
control the instrument remotely via the PC.
RS232 Interface
 Alarms/Ext Trig: as shown in the figure below, pin 1 to pin 4 is used to
output TTL pulse when an alarm is generated in the corresponding alarm
channel. Pin 6 is used to receive external trigger signal. When an external
digital multimeter is connected for measurement, pin 5 and pin 6 are used
together to control the measurement.
6
7
4
5
2
3
1
8
9
Pin
Name
Definition
1 -- --
2 RXD Received Data
3
TXD
Transmitted Data
4 DTR Data Terminal Ready
5
SGND
Signal Ground
6 DSR Data Set Ready
7 RTS Request To Send
8
CTS
Clear To Send
9 -- --