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220 / March 2000
M E T E R B R I D G E
Setting the Time
The setting controls consists of two switches: MODE and SET. To
set the clock, open the meterbridge and stand beside the console:
1) The control switches (mounted inside the meterbridge bottom) are
labelled "M" and "S". "M" ( Mode) is used to scroll from seconds
to minutes to hours; "S" is used to Set the time. The procedure is
to set the clock slightly ahead of the current time, hold the second
count at "00" until the current time catches up, and then release
the count.
2) Press the MODE button until the hour digits blink. Depress the
SET button until the desired hour is displayed.
3) Press the MODE button until the minute digits blink. Depress the
SET button until the desired minute count is displayed.
4) Press the MODE button until the second digits blink. Depress and
hold the SET button; the seconds display will hold at "00". When
the current time catches up to the display, release the SET button.
The clock will start counting. Hit the MODE button three more
times to place the clock into working mode.
Battery Backup
With the meterbridge open, note the nickel-sized round Duracell
DL2032/3V long-life lithium battery (it goes into the socket negative
side in) at the bottom of the clock display card. Note the battery does
NOT light up the clock display; it powers the clock crystal to keep it
from losing count (it will do this for 3 to 4 weeks).
Operational Modes
The standard factory default clock configuration is crystal-con-
trolled, 12 hour mode, stand-alone operation. However, the clock will
operate either from the internal crystal controlled time base or from an
ESE master (TC-76, TC-89, TC-90, autodetect) signal. Because crystal
time bases are subject to drift over time, Wheatstone recommends
operating the clock in the ESE slave mode for those applications where
the exact time is critical.
It can also be programmed to count in either 12 hour or 24 hour
modes. Connect an ESE master at connector CT3 (Pin 1 - Signal, Pin
2 - Shield). Switch #4 on SW3 sets 12/24 hour mode (Off - 12 hour, On
- 24 hour).
220 / Feb 2002