User manual

LT Series User Manual 2–5
Chapter 2 – Specifications
 Flex Network Interface (Type B/Type B+/Type C)
 Alarm Output for Circuit (All Types)
Turning the LT unit ON will start the unit’s system software and the alarm output
circuit’s relay. When a major error triggers a watchdogtimer alarm, however, this
relay will turn OFF. Since an undefined LT input or output condition can occur, be
sure to design an external failsafe circuit that will monitor the output of this relay.
For detailed information, refer to the Flex Network User Manual.
LT
ALARM
Communication
Type
1:N
Connection
Method
Multi Drop
Transfer Distance
At 6 Mbps: 200 m per CH
At 12 Mbps: 100 m per CH
Transfer Method
During cyclic period, distributed transmission, Half-duplex
Transfer Speed
6 Mbps (for 100 m), 12 Mbps (for 200 m)
Transfer I/F
Differential method, Pulse transfer resistance
Error Check
Format check, bit check, CRC-12 check
No. of Stations
63 (max.), 1008 I/O points (depending on type of units used.)
Contact Rating
0.15A – AC 125V Resistance Load
0.6A – DC 24V Resistance Load
Operating Time
(Set Time at
20
o
C)
4ms or less
Recovery Hours
(Reset Time is
set a t 20
o
C)
4ms or less
Minimum
Switching Load
1mA / DC 5V
Initial Contact
Re sista nce
100m
Ω
or less
• When the LT unit’s power is turned ON, the Alarm Output is turned OFF
for approximately 1 second. Therefore, be sure to design your circuits
so that they disregard a 1 second Alarm Output stop after the LT unit’s
power is turned ON.
Example: Insert an external timer in series with the Alarm Output that
turns OFF 1.5 seconds after power is turned ON.
For circuit design examples,
LT Series User Manual 2.2.5 External Inter-
face  Alarm Output