Telenetics MIU Dial or Leased Line modem with RS-485 Environmental Specifications, Speed Distance

5.RS485 SPECIFICATIONS

MIUXXXX/485 are low-power Transceiver for RS485 and RS422 communication

Features:	Point to Point	or Multidrop/Multipolling
	Full or Half Duplex
	Drivers are short - circuit current limited			& protected against excessive
	power
	dissipation (shutdown will places the drivers in a high - impedance state).
	When Drivers are disabled (by TXD),			drivers		will switch to		high
impedance	state.
	Note in two-wire or multi-drop/multi-polling networks TX enable by TXD
	should be active
	Receiver input impedance is 12K ohms.
	Reduced slew- rate drivers that minimize EMI and reduce reflections
caused	by improperly	terminated cables		This	will	allow	error -	free
transmitted	data up to 200Kbps
	RS485/RS422	standard covers line	lengths		up to	4000	feet. For	line
lengths
	greater than 4000 feet a line repeater		can be added.
	MIUXXXX/485 can drive 4000 feet		of 26AWG twisted - pair cable at
	200k bps into 120 ohms load.

To minimize reflections, the line should be terminated at both ends. In multi - polling/multi - drop environments (up to 32 drops) all drops off

themain cable should be as short as possible.

Only the Master/Host unit and the end of cable unit should be terminated.

Typical Speed versus Distance - (4-wire point to point 26 AWG twisted cable)

SPEED	DISTANCE
1200bps	6.0 miles(9.6 km)
2400 bps	4.5 miles (7.2 km)
4800 bps	4.0 miles (5.5 km)
9600 bps	2.5 miles (4.0 km)
19,200 bps	1.8 miles (2.9 km)
38,400 bps	1.4 miles (2.1 km)
56,400 bps	1.1 miles (1.8 km)
115,000 bps	0.6 miles (0.9 km)

NOTE: Speed and distances will depend on actual operating environment.

6. ENVIRONMENTAL SPECIFICATIONS

The CIU/485 (MIUXXX\485) meets the following environmental specifications.

Install Op and Diags for MIU Modems and RS485 (0049-0002-010A) Page 5 of 16