Myron L Aquaswitch II - Manual (Page 20)

7. ALARM/CONTROL RELAY CONNECTIONS
The Myron L Company AQUASWITCH is equipped with a “Dry
Contact” relay which is designed to energize/de-energize when
the set point is crossed. (See section IV.B.2) for set point
adjustment procedure) The relay energizes on increasing or
decreasing readings as set by the user, see section IV.B.1.
When energized (above set point), the Common (COM) will
disconnect from the Normally Closed (NC) contact and connect to
the Normally Open (NO) contact. Devices may be operated using
either the Normally Open contact or Normally Closed contact; or
both relay contacts may be used to control two devices of the
same voltage.
WARNING: CONNECTING BOTH POWER SOURCE
LEADS TO THE RELAY TERMINAL BLOCK
CONNECTERS WILL DAMAGE THE CIRCUIT BOARD
AND MAY CAUSE PERSONAL INJURY.
1. Place the user supplied Alarm relay interface cable and
watertight cable restraint into the enclosure's
appropriate access hole.
2. Neatly connect the relay interface cable wires to the
AQUASWITCH power board terminal block connectors,
see figures II.E.1 or II.E.2, and II.E.12 or II.E.13.
CAUTION: The connectors require only a small screwdriver or a
pen to push on the release levers. The release levers may be
broken or damaged if not pushed straight toward the circuit board.
DO NOT push the release levers sideways. Early models have
screw terminals.
NOTE: See Section IV.C for the “ALARM RESET” jumper
adjustments.
The easiest method of connecting the relay is shown in figures
II.E.1 or II.E.2 and II.E.12. These show how the dry contact relay
can use incoming power to activate a controlled device (alarm,
solenoid valve, etc.) of 10 amps or less.
For 24 VAC applications, the Myron L Company offers a 115 VAC
to 24 VAC transformer, Model #VR, see figure II.E.13. Other
voltages must be user-supplied.
8. CONNECTING DISPLAY HARNESS TO DISPLAY
If the installation required the removal of the display harness from
the display, the following procedure will ensure it is reinstalled
without damaging the display.
WARNING: THE DISPLAY WILL BE IRREPARABLY
DAMAGED IF THE HARNESS IS INSTALLED UPSIDE-
DOWN OR MISALIGNED. THE HARNESS MUST BE
I N S T A L L E D A S S H O W N I N F I G U R E I I . E . 1 4 .
1. Grasp connector and align wires DOWN on display or with
the small edge of the display as shown in figure II.E.14.
2. Press connector onto display pins. Ensure pins are
aligned or they may become bent. Wiggle connector
slightly “end to end” if necessary.
REASSEMBLY
1. Carefully reinstall the front panel, bottom first.
Ensure no wires have been pinched between
enclosure and front panel.
2. Reinstall the two (2) screws and tighten.
3. To operate, turn power ON.
17
DISPLAY CONNECTION
PANEL MOUNTED DISPLAY
REAR VIEW
D I S P L A Y
HARNESS
DISPLAY
Figure II.E.14
AQUASWITCH
CONTROLLER
CIRCUIT BOARD
COM
NO
COM
NO
RELAY
ALARM RELAY
TERMINAL BLOCK
NC
ALARM
115VAC
POWER
SOURCE
VR
115 to 24VAC
TRANSFORMER
Figure II.E.13
Figure II.E.12
ALARM
POWER
SOURCE AQUASWITCH
CONTROLLER
CIRCUIT BOARD
COM
NO
COM
NO
RELAY
ALARM RELAY
TERMINAL BLOCK
NC