Table of Contents
Advertisement
5. Electrical Ratings and Current
Lamp Driver Electrical Ratings
LDM modules may use either 24 VDC (regulated) or internal 5 VDC for
powering connected LEDs. 5 volt usage conserves power but is limited in the
current available to drive the LEDs. Refer to "Wiring for Lamp/LED" on page
23 for connection illustrations.
LED Current
Desired (mA)
Note: The LDM-32F drives 32 LEDs and each LDM-E32F drives 32 more LEDs. An LDM
system configured for Alarm and Trouble Display Mode and employing three expanders
could have as many as 128 LEDs, all of which are activated during Lamp Test.
Maximum Current per Driver: 100 mA (external circuit must limit current)
Maximum Voltage rating per output driver: 30 VDC
Supervised circuit (typical rating): 5 volts DC @ 0.5 mA
Bipolar Darlington Open Collector NPN Transistor
Supervision of LDM points
Any LEDs or lamps connected to the LDM-32F or LDM-E32F are not
supervised for failure. Therefore, all LEDs or lamps, must be located in the
same room as the LDM modules.
LDM-32F PN 50055:C 03/20/01
Calculations
5 Volt LED Power Limitations
Max Number
of LEDs
2
130
5
66
10
34
Table 2 Power Limitations
Number of Modules
LDM-32F
LDM-E32F
1
3
1
1
1
0
31
Advertisement
Table of Contents
