Controls
The AMS050 Air Measuring Station can be purchased with or without full factory controls. When purchased
without factory controls the AMS050 will be shipped with a Ruskin low-pressure transducer. The standard
transducer is a Ruskin RU-274-R2-VDC and is factory configured for 0-1.0 inwc (0-249 Pa) corresponding
to a 0-10VDC output. The transducer requires a power source of either 12-40VDC or 12-35VAC. Optional
transducers with LCD displays or 0-20mA output are also available.
The formula provided on the PAMS (Pressure Across Measuring Station) chart must be applied to convert
the output from the low-pressure transducer into a CFM value. Each unit is provided with a PAMS chart
developed specifically for that unit. Applying other formulas may result in greater air measurement error
and unacceptable results.
When the optional AMS070V full factory controls are ordered the AMS050 unit will ship with floating
damper actuators that are driven by two triac outputs from the controller. The AMS070V controller is fac-
tory programmed to the customer's specific requirements and accepts a 0-5V CFM setpoint input from the
building automation system (BAS). The controller will produce a 4-20MA output signal corresponding to the
actual air flow at any point in time. The controller will modulate the damper position to maintain the set-
point CFM value. The controller is equipped with an internal pressure transducer that converts the differ-
ential pressure from the air measurement station into the measured air flow value. The AMS070V controller
is housed in a 12" x 12" x 6" (305 x 305 x 152 mm) NEMA1 enclosure with a 120/208/240VAC to 24VAC
transformer. Each controller is shipped with an input output chart showing the input and output scaling for
that specific unit. Contact Ruskin with the control number to obtain the calibration charts for your specific
unit.
Optional AMS070V Control Panel Installation
1. The controller enclosure should be mounted securely on an adjacent wall or attached to the air
handling unit. The panel should be mounted within 100 feet (30.5 m) of the AMS050 to assure proper
pressure signal function. If the enclosure must be mounted more than 100 feet (30.5 m) from the
AMS050, please consult your local Ruskin representative or the company that you purchased the
device from.
2. Loosen the enclosure cover screws and remove the cover.
3. Remove the appropriate knock-outs for connection of the field wiring to the enclosure's terminal
blocks.
4. Fasten the enclosure to the wall or flat surface using the four mounting holes in the back of the
panel enclosure.
Wiring and Piping Connections
1. Connect 120/208/240VAC power supply to the AMS050 control panel L1 and L2.
2. Connect the three actuator wires as shown (see page 9). Connect the
black
(com) wire to
controller terminal
24H
. Connect the
red
wire to controller terminal
24G
(com) terminal.
Please note actuator wiring is as listed above, red 24G, black 24H.
3. Connect 0-5VDC signal from the BAS to UI (universal input) and common. Observe polarity.
4. Connect 4-20mA analog output AO and Common from the controller to the BAS system.
Observe polarity.
5. Connect pressure tubing from the controller to the airflow sensing blade, connecting the low
pressure port to the blade side nearest the damper and the high pressure port to the blade side
nearest the air straightener.
6. Optional Un-Occupied signal – connect dry contact between DI and Comm. Close contact to drive
damper closed when building is unoccupied. Open contact for normal operation.
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