Background information: Often, it is necessary to connect a standard parallel printer to an RS232 interface without a difference in potential.
The signal ground of the parallel interface of most common printer models is equipped with a direct line to the ground wire. A not insulated connection of such a printer to a measuring device can thus greatly affect the measured results, due to a ground loop. Measuring equipment that works without potential and that is not equipped with a fully isolated serial interface also provide incorrect measured results if in contact with the printer and thus the ground.
This interface works without external power supply and allows for a number of mobile applications that were previously not feasible. The currentless operation however has also a few disadvantages, as the functions are limited to the essential ones. If you require high baud rates, large security FIFO or autosensing of the RS232 parameters, we recommend the standard device #82008.
Technical background on security FIFO: The flow control (or handshake) in serial interfaces is not always carried out exactly by character, as, under certain circumstances, characters might still be transmitted after the set stop signal. This effect is normally limited to maximum 3 characters, although with older UNIX systems up to 1kByte of extra data has been measured. Missing security FIFO can result in the loss of characters or even garbled printouts.
Technical data:
Baud rate:
150 .. 19,200 baud
Data format:
7,8 data bits, no,even,odd parity
Handshake:
DTR, XON/XOFF handshake
Buffer:
0 KB
Power supply:
No need for external power adapter
Current consumption:
approx. 5 mA
Input:
9-pin SUB-D socket ready for connection to PC incl. 2m cable attached to the device
Output:
36-pin Centronics plug, interface Can be plugged directly to the printer
Housing:
Plastic housing, 75x61x20 mm
Weight:
approx. 200 g
Delivery:
1 x RS232 > Centronics interface, 5kV isolated 1x mini gender changer, #11570 1x mini gender changer, #11580
