5.2 Input/Output, Function Selection 27
I/O Connector Function Jumper No. & Position
J2 RS-232 JMP 1, Position “A”
P3 Channel A Event/1 PPS JMP 1, Position “B”*
Table 5.2: JMP1, Event Input Jumper Selection
Wiring for Channel A Event/1 PPS Usage
To use P3 as a data line to trigger the event timer, first remove R44 (see Figure 5.1) and add a wire
on the main board from the left-hand side (facing front of instrument) of where R44 was located to
JMP1, position B. Then set JMP1 to position B. It is not necessary to perform this modification
when using the main RS-232 port as an event input. Just set JMP1 to position A.
5.2.3 JMP2, Fiber Optic Output (Option 20)
Jumper JMP2 is used to control which output signal is available at the Fiber Optic rear panel
connector U46: IRIG-B Unmodulated, IRIG-B Modified Manchester, or 1 PPS. Output signals
and jumper positions are as follows:
Output Signal JMP2 Position
IRIG-B Unmodulated A*
IRIG-B Modified Manchester B
1 PPS C
Table 5.3: Fiber Optic Output, JMP2
5.2.4 JMP3, Digital Output at P3
Jumper JMP3 selects the output on P3 to be unmodulated IRIG-B, IRIG-B Manchester or 1 PPS.
See Table 5.1 for identification.
5.2.5 JMP4, Relay Control Output
Jumper JMP4 is used to control the FAULT relay function available at rear panel connector J3.
Available functions are 1 PPH, Programmable Pulse, or Fault (Fail-Safe). See Table 5.4 for output
signals and jumper positions. The OUT-OF-LOCK relay is a dedicated function.
5.2.6 JMP5, Receiver Battery (Option 02) − Obsolete
Not used on current Model 1084A/B/C clocks. Earlier clocks, with Option 02, use a circuit board
mounted Ni-Cd battery enabled with JMP5. New Model 1084A/B/C clocks use a receiver with its
own manganese dioxide rechargeable lithium (MnO
2
– Li) data backup battery. These batteries offer
approximately 1 month of battery backup service with loss of instrument power. Backup batteries
are kept charged under normal conditions from the clock power supply and have an expected life
of 5 years or more.
To Next Page
Loading...