User's Manual

12
T ROUBLE LED (#3)
Green On All 3 Output Relays Normal
Red On One or more Output Relay Off-Normal
GSM C OMM LED (#4)
On Unit registered on the network Green
Flashing Waiting for an ACK from the Central Station
Red On Unit not registered or No Cellular Network
H EARTBEAT LED (#5)
Green Flashing Unit is functioning normally
Red Flashing S1 is ON after reset
RSSI Mode: When the 2550 is placed in Received Signal Strength Indicator
(RSSI) Mode by turning Dipswitch S4 to ON, the five LEDs indicate the follow
signal strength information:
Received Signal Strength Appearance of LEDs (#1 thru #5)
≥ -40 dBm
●●●●●
#1: green, solid; #2: green, solid;
#3: green, solid; #4: green, solid;
#5: green, solid
≥ -50 dBm
○●●●●
#1: off; #2: green, solid; #3: green, solid;
#4: green, solid; #5: green, solid
≥ -60 dBm
○○●●●
#1: off; #2: off; #3: green, solid;
#4: green, solid; #5: green, solid
≥ -70 dBm
○○○●●
#1: off; #2: off; #3: off; #4: green, solid;
#5: green, solid
≥ -80 dBm
○○○○●
#1: off; #2: off; #3: off; #4: off; #5: green, solid
≥ -90 dBm
○○○○☼
#1: off, #2: off; #3: off; #4: off; #5: green, flash
≥ -110 dBm
○○○○●
#1: off; #2: off; #3: off; #4: off; #5: red, solid
≤ -111 dBm
○○○○☼
#1: off, #2: off, #3: off, #4: off, #5: red, flash
No signal
○○○○○
All OFF