...........continued
Circuit
Connector
Voltage
Current Rating
Isolation
Alarm relay
Green screw terminal
—6pin
250 Vdc max
100mA
3.75kV
Fiber
ST Fiber (multi-mode
820nm)
n/a
n/a
n/a
Administration port
RJ-45
n/a
n/a
1.5kV
Timing ports ETH1,
ETH2
RJ-45
n/a
n/a
1.5kV
12.7
Time String Specifications
This section outlines the specifications for the GridTime 3000's time strings.
The GridTime 3000 supports 12 different time strings, which can be outputted from either its RS232 serial port (Port
12) or its RS422 serial port (Port 11).
The on-time point of each serial string is accurate to within ±50 µs of UTC.
The specifications for both serial ports are given in
RS422 and RS232 Port Specifications
Table 12-4. RS422 and RS232 Port Specifications
Port
Connector
Voltage
Current Rating
Isolation
RS422 Port
RJ-12
±5 V
35 mA
2.5 kV
RS232 Port
RJ-12
±3 V-±15 V
10 mA
2.5 kV
The content specifications for each time string are given below.
NGTS Time Code
Transmitted once per minute. Sent during the last second before the minute rollover to which the data in the string
refers.
Default settings: 9600bps, 8-bit ASCII, no parity.
Definition:
TyyMMDDwhhmmx<CR><LF>
Table 12-5. NGTS Time Code Content Specification
Placeholder
Content
T
ASCII "T"
yy
Last two digits of the year: e.g. "12" = the year 2012 ASCII
MM
Month: "00" = January ... "12" = December ASCII
DD
Day of month: 01 ... 31 ASCII
w
Day of week: "1" = Monday ... "7" = Sunday ASCII
hh
Two digit hour ASCII
mm
Two digit minute ASCII
x
Time mode: "0" = Local time, "1" = UTC time ASCII
<CR>
Carriage return (HEX 0D)
Appendix A: Specifications
©
2022 Microchip Technology Inc.
and its subsidiaries
Manual
DS00004572A-page 239
