DMM6500 6½ Digit Multimeter User's Manual
Section 3: Using a remote interface
DMM6500-900-01Rev. A / April 2018
3-13
To install the communications card:
1. Turn the instrument off and disconnect the power line cord and any other cables connected to the
rear panel.
2. Position the instrument so that you are facing the rear panel.
3. Remove the slot cover plate from the slot on the back of the instrument. Retain the plate and
screws for future use.
4. Align the card with the connector toward the inside edge of the slot and slide the card into the
chassis. For the last ¼ inch, press in firmly to mate the card to the connector.
5. On each side of the card, there is a spring-loaded mounting screw. Tighten these two screws,
either by hand or with a Phillips-head screwdriver, to secure the card in the case. Do not
overtighten.
6. Reconnect the power line cable and any other cables to the rear panel.
7. Turn on the instrument.
Making connections
The RS-232 serial port can be connected to the serial port of a controller using a straight-through
RS232 cable terminated with DB-9 connectors. Do not use a null modem cable.
The serial port uses the transmit (TXD), receive (RXD), and signal ground (GND) lines of the RS232
standard. The figure below shows the rear panel connector for the RS232 interface. The table below
shows the pinouts for the connector.
Figure 24: KTTI-RS232 panel view
Figure 25: RS-232 panel connector
Pin
Description
1
No connection
2
TXD, transmit data
3
RXD, receive data
4
No connection
5
GND, signal ground
6
No connection
7
No connection
8
No connection
9
No connection