Liebert RCM8DO - Manual (Page 10)

4 • User Manual (7/99)
Communications Ports
The RCM8 has five physical connection ports:
• EIA-232 (PC/Terminal) Port (DCE)—Accommodates a
personal computer or VDT for setup and message display
Refer to Chapter 2 of this
manual and the section
immediately following for
information on installation and
configuration using these
communications ports.
• EIA-232 Modem Port (DTE)—Accommodates a modem
for alarm reception and remote message transmission
• EIA-485 Port—Allows multiple RCM8 units to be "daisy-
chained" together using twisted-pair wires
• EIA-422 SiteScan Port—Accommodates a Liebert
SiteScan connection
• Common Alarm Relay Output—Accommodates a
secondary warning device
Refer to Figure 1 Component Arrangement, and Figure 3
Physical Connections and DIP Switches.
Common Alarm Relay
Output
The common alarm relay output is used to connect to a
secondary warning device -- such as a horn or light, up to 3
Ampere @ 24 Volts DC -- that activates on alarm. When an
alarm is present, the contacts close and the external warning
device is activated. The common alarm relay may be reset using
the Silence/Reset switch.
Alarm Relay Outputs
(RCM8DO only)
On RCM8DO models, one relay output corresponding to each
alarm channel is provided. There is no additional programming
logic or setup involved: each Form-A Normally Open (N.O.)
relay will energize when the corresponding channel goes into
alarm and the front panel LED is illuminated. The relays are
rated for up to 1 Ampere @ 24Volts DC.