Cambridge Air Solutions M Series, Техническое руководство

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Cambridge Air Solutions. 88 M-Series Technical Manual
GAS CONTROL SYSTEMS
Maxitrol Series 14
The Maxitrol Series 14 controls
electronically modulate the burner
input to maintain a selected
discharge temperature. The
discharge temperature is set on the
amplifier (AD1014) between 55°F
and 90°F with the standard controls.
As an option, the discharge
temperature can be set on a Remote Heat Adjust (TD114)
control between 55°F and 130°F. The Remote Heat Adjust
control can be mounted in the heater control enclosure or
in the Remote Control Station.
Maxitrol Series 44
The Maxitrol Series 44 controls
electronically modulate the burner
input to maintain a constant space
temperature by increasing or
decreasing the discharge
temperature. The Space
Temperature Selector (T244A) is
set to maintain the space
temperature of the heated space by controlling the heater
output between the MIN and MAX setting on the amplifier.
The MIN dial setting determines the minimum discharge
temperature the heater will deliver (40°F to 80°F). The
MAX dial setting determines the maximum discharge
temperature the heater will deliver (80°F to 140°F)
Intermittent/Continuous Control (ITC)
The Intermittent/Continuous Control allows the burner
input to be modulated to be operated continuously at
modulating discharge temperature for make-up air (see
Maxitrol 44 above) or operated intermittently based on a
thermostat at maximum discharge temperature for space
heating.
Requires Maxitrol 44 controls and a signal to switch
between modes (Exhaust Fan Interlock, Temperature
Setback System, Manual Make-Up Air Switch, etc.)
Signal Conditioner (SC25S)
The SC25S analog signal conditioner converts a 0-10
VDC or 4-20 mA control signal to an output level
capable of driving the Selectra modulating gas valve
(M511, M611 or MR212). A 3-position DIP switch
configures the SC25S for a 0-10 VDC or 4-20 mA input
signal.
A timer circuit initially fixes the modulator output to
0 VDC or 20 VDC whenever 24 VAC is applied to
the SC25S by an external source. After the start time
interval has elapsed, the modulator output voltage is
proportional to the control signal input. The start time
interval is user selectable between 5 and 30 second.
The SC25S monitors and limits minimum and maximum
discharge air temperatures. The SC25S senses the
discharge air temperature using a TS194 (Q) sensor w/
MT mixing tube. If the sensed discharge air temperature
approaches the set minimum or maximum limit, the
SC25S will override the control signal and reduce DC
voltage (high limit) or increase DC voltage (low limit)
in order to maintain discharge air temperatures between
the set limits. When measured discharge air temperature
is between the limit settings, the DC output is a function
of the control signal (4-20 mA, 0-10 VDC) only.