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MOBILTEX® DATA LTD.
TITLE:
Installation and Operating Instructions
Calgary, Alberta
DOCUMENT NO.:
SPI1-MAN-001
SHEET:
38 of 57
REV:
1.14
power to the SPI1, favour using relay port A for that particular connection so that the SPI1 can synchronize interruption
to the AC waveform.
Once connected to the relay device, connect the relay device to the rectifier as needed to stop current flow during
interruption. Ensure that relay power limits are adequate for the particular rectifier that is being interrupted.
Install all electrical equipment in accordance with locally applicable electrical and safety codes.
4.5 Manual Interruption
Prior to the start of interruption, ensure that the SPI1 has locked to the GPS satellite time source. This can be
determined by observing the main status screen ‘SAT:’ field value. If an asterisk (*) follows the number of satellites,
then the SPI1 has a valid time lock. The ‘UNLOCKED’ LED indicator may also be observed to determine the same
information—the LED will turn off once the SPI1 has a valid time lock. This initial satellite lock may take up to 13
minutes when the unit is in good satellite coverage. If the unit has been listening to the GPS data stream within the
prior two week period, then the lock time will be substantially less than this (typically less than 2 minutes).
This most basic way to start interrupting with the SPI1 is to use the manual interruption mode. Three pieces of
information must be entered—cycle time, off time, and duration. Separate keys are provided on the SPI1 keypad to
allow quick entry of these parameters. Cycle time is the number of milliseconds that comprise the total of the on and
off times for interruption. Off time is the number of milliseconds that the rectifier is interrupted during each cycle.
Duration is the number of minutes that the SPI1 will continue performing interruption cycles after the operation is
initiated. Enter all three parameters as required for the current pipeline survey.
***Important Notice***
If the SPI1 is being used in conjunction with other manufacturers’ interrupters, it is important that the cycle
time selected be evenly divisible into 60s, otherwise synchronized interruption may not occur. Some
manufacturers’ interrupters re-synchronize at the top of the minute, top of the hour or top of the day. The
SPI1 re-synchronizes at the top of the minute. As long as the cycle time is evenly divisible into 60s,
synchronization is assured among different manufacturers’ interrupters. Example cycle times that meet this
criteria: 100ms, 200ms, 250ms, 500ms, 1000ms, 2000ms, 3000ms, 4000ms, 5000ms, 6000ms, 10000ms, 12000ms,
15000ms, 20000ms, 30000ms, 60000ms. Also, some manufacturers start an interruption cycle at the reference
point with the rectifier on-time occurring before the rectifier off-time—in this case, set the ‘ON 1ST’ parameter
in the manual schedule ([MENU][2][0]).
To start interruption once the parameters have been entered, press the [MANUAL START/STOP] key. The ‘MODE:’
field on the main status screen should change to ‘MAN’, indicating that the manual schedule is active. The
‘INTERRUPT’ LED should light during the off portions of the interruption cycles.
To stop manual interruption early, press the [MANUAL START/STOP] key. The ‘MODE:’ field should return to
‘IDLE’.
4.6 Scheduled Interruption
The SPI1 includes a scheduler system to allow more flexible field use. The SPI1 can be programmed with up to seven
separate schedules, each with independent cycle, off, and duration times. Each schedule may also be set to repeat
daily.
Schedules are configured by entering the schedule configuration menu. From the main status screen, press [MENU][2]
followed the schedule identifier number. A menu will be presented with the options for the schedule being changed.
The first parameter is the start time for the schedule; this is entered as month/day/hour/minute. The next three
parameters are the same as those available in manual mode, duration, cycle time and off time. The next parameter is
the daily repeat—when this parameter is set, the month and day portion of the start time are ignored, causing the
schedule entry to start operation every day at the set time. The final parameter is the schedule enable—when set, the
schedule is placed in an operational state. If the schedule enable is set to no, then the schedule is ignored.
***Important Notice***
If the SPI1 is being used in conjunction with other manufacturers’ interrupters, it is important that the cycle
time selected be evenly divisible into 60s, otherwise synchronized interruption may not occur. Some
manufacturers’ interrupters re-synchronize at the top of the minute, top of the hour or top of the day. The