Model DT33x-0700
4-Wire DC I/V Dual Transmitter w/USB
Acromag, Inc. Tel: 248-295-0880
- 35 -
http://www.acromag.com
- 35 -
https://www.acromag.com
USB Interface
USB MINI-B socket for temporary connection to a PC or laptop for configuration and
calibration purposes. USB isolation is required when input is connected to a
grounded input sensor (see
“IMPORTANT”
below). During reconfiguration &
recalibration, the transmitter receives its power from its DC power connection (via
DIN rail bus or power terminal TB5), not USB. As such, you must connect power to
the unit when you connect USB.
CAUTION:
Do not attempt to connect USB in a hazardous environment. Transmitter
should be set up and configured in a safe environment only.
Data Rate:
USB v1.1 full-speed only, at 12Mbps. Up to 32K commands per second.
USB 2.0 compatible.
Transient Protection:
Adds transient voltage protection on USB power & data lines.
Cable Length/Connection Distance
: 5.0meters maximum.
Driver:
No special drivers required. Uses the built-in USB Human Interface Device
(HID) drivers of the Windows Operating System (Windows XP or later versions only).
USB Connector:
5-pin, Mini USB B-type socket, Hirose UX60-MB-5S8.
USB PIN
DEFINITION
1
+5V Power (Transient Protected, but not used by the module)
2
Differential Data (+)
3
Differential Data (-)
4
NC
–
Not Connected
5
1
Power Ground (Connects directly to Signal Ground)
SHLD
1
Signal Ground (Connects directly to Signal Ground)
1
Note:
Most Host Personal Computers (except battery powered laptops) will connect
earth ground to the USB shield and signal ground.
IMPORTANT
–
USB Isolation is Required:
Each input of this unit is isolated from
each output and may be connected to grounded or un-grounded input sensors, but
the input 1 circuit ground connects in common to the USB power/signal/shield
ground. This will in-turn make a connection to earth ground at the PC when directly
connected to the USB port of a Personal Computer if you do not use an isolator.
Failure to connect USB without isolation would short the 1.25V input return bias
supply of input 1 to ground if the sensor is also earth grounded, interfering with
operation of channel 1, truncating its negative input range, and possibly shifting its
output. For this reason, USB isolation is strongly recommended when connecting to
a PC. In the absence of USB isolation when connected to a grounded input sensor at
CH1, a battery powered laptop could be used to connect to the unit instead, as the
laptop does not normally connect to earth ground.
!
