Schreiber Engineering 300AC-MRI, Owner'S Manual

Page: 9 / 46

SETTING SOLID STATE CONTROL
This unit has a solid-state control that controls the temperature on the refrigeration
system. After the unit is wired to the proper voltage the control temperature and high
temperature alarm can be set.
1.
On the front of this control is the temperature display, to set the temperature
press and hold button #2 while turning the set point screw above button #2. The
temperature display will indicate the set temperature as you turn the set point
screw.
2.
To set the high temperature alarm press and hold button #3 while turning the set
point screw above button #3. The temperature display will indicate the set
temperature for the high temperature alarm
as you turn the set point screw.
We suggest you keep the differential, between the temperature and the alarm, at 5
0
F
then set the alarm temperature at 60
o
F. The alarm will sound at 60
o
F.
3.
Press button #4 to turn the alarm off if necessary. After the cause of the alarm
has been found, be sure to turn the alarm back on.
4
Alarm Feature. – The high temperature alarm does not function when the
compressor and water pump switch is in the “off” position., for example, during
the night shut down. When the compressor and water pump switch is turned on
in the morning, the alarm will not sound even if the water temperature is above
the set point, however, the red fault light (number four on page 8) will remain on
until a temperature below the set point is reached. The audible alarm will sound
again unless the water temperature rises again above the set point.
CHECKING TEMPERATURE SET POINTS
To check temperature set points just press #2 for compressor and #3 for alarm set
points.
CAUTION
Check low voltage, this is a 24 Volt system. Be sure you check the 24 Volt circuit at the
main panel and remote panel.
REMOTE WIRING – SOLID STATE CONTROL
This unit is designed for remote control. We have supplied the wire to connect the main
water chiller control panel to the remote panel. Make sure you connect the remote wire
colors to match the terminal block. in the electrical enclosure. There is a diagram insert
with colors to match the numbers on the terminal block.. The thermocouple wire is a
special wire and cannot be spliced to other types of wiring. The main control panel has
pilot