Setting the Digital 8-Port Timer

These notes describe the operation of the 8-port valve with digital timer, ie. the Randall and Sangamo types.

This contains a rechargeable battery which maintains the clock time and programmed sequences in the event of a temporary mains power failure. There should therefore be no need to have to reset time and switching sequences after a power failure. However, a power failure will cause the pump to stop for some time, and hence the volume of air sampled by the affected filter and bubbler will be less than expected. Mains power is also required at all times to drive the valve changeover motor, so if the power is off at the time set for valve change, the changeover will not occur, even though the time switch continues to run uninterrupted. This will result in the same filter and bubbler being used continuously for more than 24 hours. For this reason, always check that the expected bottle is bubbling when you make your routine visit.

The red circular push button on the face of the unit below the time switch is used for manually changing valve ports. Depressing this button will illuminate the neon indicator: the button should be held down for 1 second until the neon remains ‘on’ when the button is released. The motor will then continue to drive the valve to its next position when the neon will go ‘off’. Do not attempt to use the manual changeover button when an automatically timed changeover is about to take place.

The procedure below should be used when it is necessary to set up the Randall or Sangamo E1 programmable time switch. The steps in block capitals (eg PROG, CANCEL, EXIT etc) mean that the appropriate red, rectangular control button must be pressed once and once only. To get at these buttons it may be necessary to open the grey plastic cover at the front, using a small screwdriver. The steps must be followed in the numbered sequence. Press the control buttons gently but firmly in the centre ; take care not to jam the button in a permanently ‘down’ position. You may find it easier to use the blunt end of a pen or pencil, rather than your finger.

If it is necessary only to set the correct GMT time of day, follow Stage 1 steps 1 to 8. Stages 2, 3 and 4 can be omitted if the switching sequences are already set correctly. Altering the time of day has no effect on the daily programmed or copied switching sequences.

If the GMT time of day is correct, but it is required to set the programmed times of operation, omit Stage 1, steps 1 to 8, and start at Stage 2, step 9.

Steps enclosed in square brackets [ ] can be omitted if the selected flashing option is already correct, but all other steps must be completed.

Stage 1: Setting correct GMT clock time (when necessary)

1. TIME

[ 2. DAY]

[ 3. INC/DEC until correct day flashes]

[ 4. HR]

[ 5. INC/DEC until correct AM or PM hour flashes. Note: If BST is in effect, subtract 1 hour, eg 1254 BST is 1154 GMT]

[ 6. MIN]

[ 7. INC/DEC until correct minutes flash]

8. ENTER

Time is now set: this is the normal ‘RUN’ mode.

Stage 2: Clear all day and copied switching sequences

9. PROG

10. CANCEL

11. CANCEL

12. COPY

13. CANCEL

14. CANCEL

T he time switch is now completely cleared of all programmed switching sequences.

Stage 3:

15. PROG

[ 16. INC/DEC until ON/OFF mode 1 symbol flashes]

17. ENTER

18. SET ‘program level 21’

19. DAY

[ 20. INC/DEC until MON flashes]

21. HR

22. INC/DEC until PM hour 11 flashes

23. MIN

24. INC/DEC until minutes 58 flashes

25. ENTER sets ON time of 1158 pm; switch status 1 ‘ON’ changes to 0 ‘OFF’

[ 26. HR]

[ 27. INC/DEC until PM hour 11 flashes]

28. MIN

29. INC/DEC until minutes 59 flashes

30. ENTER sets OFF time of 1159 pm which will actually take effect 1 minute later at midnight; ‘program level 21’ changes to ‘programme level 20’

31. EXIT

32. EXIT

Monday is now set in ON/OFF mode to trip at 1158 pm and start valve movement at midnight GMT.

Stage 4: Copy Monday’s program into Tuesday through Sunday.

33. COPY

34. SET

35. DAY

[ 36. INC/DEC until MON flashes]

37. ENTER the ‘base’ day is now Monday

38. INC/DEC until TUE flashes

39. ENTER Monday’s program is copied into Tuesday

40. DAY MON should flash (the ‘base’ day)

41. ENTER

42. INC/DEC until WED flashes

43. ENTER Monday’s program is copied into Wednesday

44. DAY MON should flash (the ‘base’ day)

45. ENTER

46. INC/DEC until THU flashes

47. ENTER Monday’s program is copied into Thursday

48. DAY MON should flash (the ‘base’ day)

49. ENTER

50. INC/DEC until FRI flashes

51. ENTER Monday’s program is copied into Friday

52. DAY MON should flash (the ‘base’ day)

53. ENTER

54. INC/DEC until SAT flashes

55. ENTER Monday’s program is copied into Saturday

56. DAY MON should flash (the ‘base’ day)

57. ENTER

58. INC/DEC until SUN flashes

59. ENTER Monday’s program is copied into Sunday

60. EXIT

61. EXIT

Every day of the week is now set to be a copy of Monday.

The switch status (below AM/PM) should now be 0 for OFF, and the red LED on the right hand side of the LCD display should be ‘off’. It status is 1 for ON and the LED is ‘on’, press O/R once.

IMPORTANT: DO NOT TOUCH THE ‘CONTINUOUS OFF BUTTON’

If required, use the manual changeover button to step the valve until the desired bottle is seen to be bubbling.

What to do if you make a mistake in the setting sequence

Press ENTER/EXIT . . . . EXIT until the LCD display shows normal time-of-day ‘RUN’ mode. Then start again from the beginning of Stage 2.

To review the sequence programmed for Monday, without altering anything:

62. PROG

63. REVU

64. INC/DEC to view the 1 ‘ON’ and 0 ‘OFF’ settings

[ 65. DAY]

[ 66. INC/DEC to select another day]

[ 67. ENTER]

[ 68. INC/DEC to view the selected day’s settings]

If you are curious, steps 65 through 68 may be repeated to examine any other day of your choice.

69. EXIT

70. EXIT to normal ‘RUN’ mode.

Note: the only day intentionally wet with an ON/OFF sequence is Monday. Tuesday through Sunday will normally show no programmed sequence, indicated by a displayed set time of 0:00.

To review days using a copied program, without altering anything:

71. COPY

72. REVU MON, the ‘base’ day, should appear solid, while TUE through SUN should all flash, indicating that they are copies of Monday’s sequence.

73. EXIT

74. EXIT to normal ‘RUN’ mode.

Footnote

Only the defined sequences above should be used. The Randall / Sangamo time switch can be programmed in other ways, but these are not recommended for this application.



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