DIP Switch Position Table
Control
Signal
SW1
Signal
SW2
Offset
SW3
Characteristic
0-10V
OFF
OFF
OFF
2-10V
OFF
ON
OFF
0-20 mA
ON
OFF
OFF
4-20 mA
ON
ON
OFF
2
© 2019 Maxitrol Company, All Rights Reserved.
EXA Modulating Valve Series
The PWM output will give a feedback to correspond with the
current valve position between the programmed minimum and
maximum positions. The duty cycle range is always scaled
from the programmed minimum to the programmed maximum
position.
Frequency:
200 Hz ± 1 Hz
Resolution:
9-bit (0.29% duty cycle)
Duty Cycle:
3% @ programmed minimum position
97% @ programmed maximum position
Output Impedance:
3.2 kΩ ± 0.1 kΩ
Output High Voltage:
5.0 V nominal
5.25 V maximum
NOTE:
Output high level varies with the load current at the
PWM output.
Output Low Voltage:
0.0 V + 0.01 V
Pin 1: (+) positive polarity
Pin 2: (-) negative polarity
(see Figure 2)
Connection:
TYCO MTA-100 or EQ.
NOTE:
Optional pre-wired connector for control signal/power/
feedback available. Contact Maxitrol Customer Service
for details and availablity.
Table 3: Dip Switch Position Table
Flow Capacity in Btu/h @ 1” Pressure Drop:
Model
Nat Gas
LP
EXA40 (3/8”)
190K
315K
EXA40 (1/2”)
215K
355K
EXA50 (1/2”)
385K
640K
EXA50 (3/4”)
435K
725K
EXA60 (3/4”)
670K
1115K
EXA60 (1”)
780K
1300K
Table 1: Sizing Chart
SPECIFICATIONS CONTINUED
Sizing
Valve sizing and selection is based on the typical 1.0” w.c.
pressure drop allowance at maximum flow rate. Using the sizing
chart (table 1), find the closest flow rate which meets or exceeds
the appliance’s maximum modulated flow rate.
POSITION FEEDBACK OUTPUT SPECIFICATION
Figure 2: EXA Modulating Valve Series Connections
Power:
Terminal 4
Terminal 3
Position Feedback:
Pin 1
Pin 2
Control Signal:
Terminal 1
Terminal 2
DIP Switches
(Table 3)
Table 2: Connection Table
© 2019 Maxitrol
Control Signal
The control signal indicates a position within the valve’s
programmed range of modulation.
NOTE:
Control signal is polarity sensitive. Connect control
signal positive (+) to terminal 1 and control signal
return (-) to terminal 2 (see table 2).
The control signal is “scaled” between the high and low fire
setting of the valve. The minimum control signal will correspond
to the programmed low fire setting, and the maximum control
signal will correspond to the programmed high fire setting.
Connection Table
Terminal 1
Terminal 2
Terminal 3
Terminal 4
Signal (+)
Signal (-)
Power (+)
Power (-)
DIP Switches
A three (3) position DIP switch is located on the PCB (see Figure
2). Change the signal type and offset by changing the position
of DIP switches. (For DIP switch position and corresponding
current/voltage ranges, see Table 3).
