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Self-Diagnostic Tests:
The Model 1250B regularly performs several self-check
diagnostic tests and generates error codes in the form “FA
n
” and “ERR
n
” if it detects an
internal fault. The “
n
” number indicates the type of failure detected. See Section 5.0 for a
full list of error codes and their explanation.
Power Fail:
The 1250B is designed to shut its microprocessor off when it detects the
line voltage falling below a fixed threshold, typically 85 to 105 VAC. This feature enables
the microprocessor to properly store its data before the power is lost completely. The 1250B
will automatically re-start itself when the line voltage rises above the Power Fail Threshold
voltage.
Firmware Revision:
The revision number can be displayed by pressing the
“SELECT/ENTER” key while turning on the power to the 1250B.
Cold Boot:
The 1250B has the capability to delete all user-programmed values and
restore all factory default program values. This “cold boot” is accomplished by pressing the
“MENU” key while turning on the power to the 1250B. There is no way to undo the effects
of a cold boot.
LED Test:
The display can be tested. Use the
OP 40, LED t, LEDTEST
command to
turn on all display LED’s. Press the ENTER key to stop the test.
RS-232 Port Test:
The RS-232 serial port can be tested. Use the
OP 41, RS t
menu
command to enter the
RS-232 Echo Test mode. With a computer terminal connected to the
serial port, type in some characters. The 1250B should receive these characters and re-
transmit them back to the terminal. The characters typed should appear on the terminal
display. Press the ENTER key to stop the test.
Relay Test:
The High / Low relays can be tested. Use the
OP 43, RLY t, RLYTEST
command to turn on one of the relays. The UP and DOWN keys will cause the 1250B to
toggle between the High and Low relay. If you are using the RS-232 serial port, press the
space bar on the computer terminal to toggle between the High and Low relay.