Herrmidifier Herrmersion RE - Manual (Page 19)

Herrmersion RE
I n s t a l l a t i o n , O p e r a t i o n , & M a i n t e n a n c e M a n u a l
19 www.herrmidifier-hvac.com
a 0-5VDC demand signal sent from another control system;
such as a building management system or DDC controller.
A unit configured for “I” is ready to accept 0-5VDC input
signal(s) from a humidity transmitter and a high limit humidity
transmitter. The unit will then modulate the unit according to
the setpoint entered by the operator.
• P/I Control – The Administrator may change the unit
control type so that the unit will react to a demand signal
from an external control system or the unit can control
itself according to an operator setpoint by reacting to a
signal from a humidity transmitter connected directly to
the control board.
• Overfill – The Administrator may adjust the length of a
fill cycle using this configuration parameter. Default =
60s. This is the length of time the fill valve will remain
open during a fill cycle plus the skim time set in the
Parameters menu.
• Interval – This allows the Administrator to change the
interval at which the PID loop calculates and updates the
unit output. Default = 60s. Increasing this time will slow
down the reaction time of the unit. Decreasing this time
will cause the unit to react faster to changes in humidity
level.
• P-Gain – The Proportional Gain adjusts the control band
in which the unit will begin to adjust capacity. As the
sensed humidity approaches the setpoint, the unit will
reduce the output percentage.
• I-Gain – The Integral Gain changes how the controller
will adjust the output percentage as time passes during
operation. If the setpoint is not achieved quickly enough,
increasing this gain will cause the unit to increase the
output percentage.
• Deadband – This may be adjusted to allow for a range
of input percentage or setpoint where no action is to be
taken. Default = 0%.
• Ramp Time – This Ramp Time allows the system to be
slowed by setting a minimum allowable time for the unit
to ramp from 0 to 100% output. Default = 0%.
Alarm Descriptions
The following alarm messages may appear. Refer to the
specific alarm message below for a description of what
circumstances will cause the alarm to become active.
• AF Switch Open: Upon a call for humidity or anytime
during the operation of the humidifier, if the air proving
switch opens, the unit will cease to produce steam until
the air proving switch closes again; indicating that airflow
is present again.
• EOS Drain: If a call for humidity is absent for greater
than 72 hours, the humidifier will drain the tank and
shutdown. Upon a new call for humidity, the unit will
refill the tank and commence normal operation.
• High Humidity: If the high limit humidity transmitter value
falls below the HL Fault setpoint (in CONFIG menu),
the unit will cease to produce steam. This will indicate
a problem with the sensor only. The default setting is
5% rh. This alarm can only become active on units
configured for proportional + integral control (RES-I).
• Low Humidity: If the controlled humidity falls below the
low humidity setpoint, the unit will cease to operate until
the problem is corrected and the alarm is acknowledged
and reset via the ON/OFF switch.
• Slow Drain: If during a timed drain cycle, the upper water
level float switch remains closed. This alarm will become
active thirty seconds before the end of the timed drain
cycle. The unit will cease to operate. The operator
should verify that the drain line is clear by invoking a
manual drain cycle. If the drain is open, the alarm may
be reset via the ON/OFF switch. The unit will return to
normal operation.
• Slow Fill: During any fill cycle, if both water level float
switches do not close within thirty minutes, this alarm
will become active. This may be caused by low water
pressure, an obstruction in the fill line, or a failed fill
solenoid valve. The unit will cease to operate until the
alarm is reset via the ON/OFF switch.
• Timed Drain: During any timed drain cycle, the alarm
light will illuminate for the duration of the drain cycle.
This is to provide indication only. The drain cycle will
be time stamped and stored in the ALARM screen of the
display module. No user intervention is needed. The unit
will commence normal operation upon the completion of
the drain cycle. Timed drain cycles may be deactivated
via the keypad.
• Water Lvl Err: This alarm indicates that the float switches
may be dirty and stuck open or closed. If the upper water
level float switch is closed and the lower water level float
switch is open, this alarm will become active. The tank
should be cleaned and the float switches checked for
proper operation. The alarm may be reset via the ON/
OFF switch.