Model: MC-1-DE
Doc Ref. No:-m05dom102
Issue No:-00
User’s Manual
Page 68 of 76
12. Holdover Mode
If GPS TIME SYNC UNIT MC-1-DE is Power ON in Unlock conditions, the unit will provide time out-
put depending on the data of its internal RTC clock time which is available with battery backup (refer
section 7.2). However, if the provided battery backup to RTC is discharged due to very long Power
OFF period so at Power ON conditions in unlock conditions all outputs of MC-1-DE device will have
factory set time value and not the correct time, so when MC-1-DE device gets locked, all outputs will
get proper time data.GPS TIME SYNC UNIT MC-1-DE device enter Holdover mode, when unit goes
into Unlock condition from Lock condition and thereafter provides time output depending on the inter-
nal clock crystal accuracy. The accuracy of all time outputs (including 1PPS output) of unit will de-
grade depending on the duration during which unit is in Holdover mode and also on the internal clock
crystal frequency accuracy. If the Unit again enter the Lock condition from Unlock condition, all the
time outputs will become accurate as per UTC time. Holdover mode conditions do not exist if GPS
TIME SYNC UNIT MC-1-DE unit gets power reboot while unit was in Unlock condition. GPS TIME
SYNC UNIT MC-1-DE outputs will regain its accuracy only when unit gets in lock condition once after
Power ON.
