Integrated Drain and Control Module - Features
1.   May be easily retro-fitted to existing Electrosonic humidifiers.
2.   Integral low voltage drain unit for safety and ease of installation.
3.   Timer unit offers automatic drain down on a regular basis or else after
     humidification has not been required for a set period.
4.   Timer period* may be set at 1.5, 3, 6, 12, 23, 47 or 93 hours approximately.
5.   The drain open time can be set to either 10 or 20 minutes.
6.   Because the timer starts timing when the unit is switched on and is not set to
     chronological time, it is not necessary to set a clock.  In a multi-unit installation, it
     is most unlikely that more than one humidifier would be drained down at the same
     time when humidification is required.
7.   The solenoid valve is controlled by a triac and is arranged to switch only as the
     incoming AC supply passes through zero volts.  This reduces electrical
     interference generation.
8.   The relay controlling the supply to the transducers is electronically controlled so
     that it switches close to the zero volt crossover.  Apart from reducing interference,
     this also prevents arcing of the relay contacts and prolongs contact life.
9.   A capacitor in the module stores sufficient energy to open the drain valve in the
     event of a loss of power to the unit.  A capacitor is used rather than a battery as it
     has an indefinite service life and is charged within minutes of being switched on.
10.  All terminals are clearly marked and easily accessible.
11.  As the float switch contacts only handle a few milliamps, their life should be
12.  The humidifier may be controlled directly by a room humidistat without the need
       for a power relay.  Alternatively it may be controlled by switching the 48v supply
       to the unit.
13.  BMS compatibility is an integral feature of the control unit.
     Output signals from the controller board may be used to transmit the status of the
     following to a BMS system:-
          a)   Drain valve open
          b)   Solenoid valve open
          c)   Transducers operating.
     (A simple interface unit may be required depending on the requirements of the
     BMS system.)
     A signal from the BMS system may be used to control the transducers without the
     need for intermediate relays.
     The same signals may used with a standard display and power supply panel.
14.  A 10,000 hour elapsed time indicator may be built into the unit to indicate the
     total running hours of the transducers.
15.  The integration of the various functions into one unit simplifies the external
     control panel and in many cases will render one unnecessary.

* Exact timer periods:-
     0 days    1 hours   27 minutes
     0 days    2 hours   54 minutes
     0 days    5 hours   49 minutes
     0 days    11 hours  39 minutes
     0 days    23 hours  18 minutes
     1 days    22 hours  36 minutes
     3 days    21 hours  12 minutes     
 jht/bsd 17:10:2002