Product Overview

ManualsBrandsJohnson Controls ManualsA350 Temperature ControlsProportional Temperature Control, -30F to 130F 0-10VDC, 4-20MA

FANs 930, 930.5, 125, 121

Product/Technical Bulletin A350P

Issue Date 0899

Part No. 24-7664-192, Rev. F www.johnsoncontrols.com

Code No. LIT-930020

The A350P is an electronic, proportional plus integral

temperature control with analog 0 to 10 VDC and

0 to 20 mA outputs. The control is equipped with

three user-selectable time integration constants and

an adjustable throttling range of 2 to 30F° (1 to 17C°).

Two models cover a setpoint range of -30 to 130°F

(-35 to 55°C) and 90 to 250°F (32 to 121°C).

As are all System 350

™

products, the A350P control

is housed in a NEMA 1, high-impact plastic enclosure.

The modular design provides easy, plug-together

connections for quick installation and future

expandability.

Figure 1: A350P Electronic Proportional Plus

Integral Temperature Control

Features and Benefits

❑

Modular Design

Enables stage, display, and power modules to

be purchased and installed as needed

❑

Plug-Together Connectors

and 35 mm DIN Rail

Mounting

Eliminates wiring between modules, which

reduces installation costs

❑

Two Models Cover a Wide

Setpoint Range of -30 to

250°F (-35 to 121°C)

Reduces inventory by encompassing

temperature ranges required to support the

majority of Heating, Ventilation, Air Conditioning,

and Refrigeration (HVAC/R) applications

❑

Minimum Output Adjustable

from 0 to 60%

Tailors the output to the requirements of the

controlled device; can be used to set minimum

valve or damper position

❑

Adjustable Throttling

Range of 2 to 30F° (1 to 17C°)

Enables the user to tune the system for optimum

stable performance

❑ Field-selectable Reverse

or Direct Acting Mode

Works in heating or cooling applications

❑

Three User-Selectable

Integration Time Constants

Provides selection of the integration constant for

applications requiring proportional plus integral

control

❑ Interchangeable

Temperature Sensors

Increase versatility and serviceability

System 350

A350P Electronic Proportional Plus Integral

Temperature Control

Summary of content (12 pages)

PAGE 1
FANs 930, 930.5, 125, 121 Product/Technical Bulletin A350P Issue Date 0899 System 350TM A350P Electronic Proportional Plus Integral Temperature Control The A350P is an electronic, proportional plus integral temperature control with analog 0 to 10 VDC and 0 to 20 mA outputs. The control is equipped with three user-selectable time integration constants and an adjustable throttling range of 2 to 30F° (1 to 17C°). Two models cover a setpoint range of -30 to 130°F (-35 to 55°C) and 90 to 250°F (32 to 121°C).
PAGE 2
A pplication O peration The A350P Temperature Control can be used as a standalone device or in conjunction with plug-together accessory modules. The addition of S350 Stage Modules allows for the control of multiple stage HVAC/R applications. Typical application for the A350P includes: The A350P control operates on 24 VAC/VDC and provides two simultaneous analog outputs: 0 to 10 VDC and 0 to 20 mA. A cover-mounted, 10-segment Light-Emitting Diode (LED) bar graph indicates percentage of output.
PAGE 3
Minimum Output Adjustment Throttling Range (Proportional Band) The minimum output adjustment sets the minimum voltage or milliampere output provided by the A350P control. It can be adjusted from 0 to 60% (0 to 6 VDC or 0 to 12 mA) of the output range. The throttling range is the range over which a control is active. Throttling range for the A350P control can be adjusted from 2 to 30F° (1 to 17C°). Make the adjustment at the throttling range potentiometer marked THROT RANGE (see Figure 2).
PAGE 4
Temperature Proportional Only Control System Load Proportional Offset Load Change Control Point Follows the Load Throttling Range Setpoint Time Proportional Plus Integral Control Temperature Proportional Offset = 0 System Load Load Change Integration adjusts the proportional output to bring the process to setpoint regardless of load.
PAGE 5
Reverse or Direct Acting Operation With the operation jumpers in the Reverse Acting (RA) position, the analog output increases as the temperature drops below setpoint. (See Figure 5.) With the operation jumpers in the Direct Acting (DA) position, the analog output will increase as the temperature rises above the setpoint. Select the RA/DA mode by positioning the operation jumpers vertically or horizontally. (See Figure 2.) Position the operation jumpers vertically for RA and horizontally for DA.
PAGE 6
D imensions 3/16 (4) Mounting Slots for No. 6 Screws 1/2 (13) 5 (127) 2 15/16 (75) 1 9/16 (40) A350P 4 (102) 2 3/8 (61) DIN Rail Mount 7/16 (11) 1 3/16 (31) 3 (76) Sensor 1/4 (6) 9 3/4 (248) 2 3/8 (61) 2 (50) 7/8 (22) Conduit Hole 7/8 (22) Figure 6: A350P Control and Sensor Dimensions, in. (mm) I nstallation and Wiring Celsius Scale Conversion A Celsius scale throttling range decal is included with the A350P control. If the Celsius scale is desired: 1.
PAGE 7
Wiring Terminals Sensor Connection Install all wiring to conform to the National Electrical Code and local regulations. For maximum electrical rating of control, refer to the label inside the control cover. Terminals will accept 12 to 26 AWG wire. Use only copper conductors. Shielded cable is not generally required for sensor wiring on runs of less than 50 feet. When using shielded cable, isolate and tape the shield at the sensor. Connect the shield to Terminal C on the A350P control. 1. Use a 1/8 in.
PAGE 8
A djustments Follow this procedure to set up the A350P control for the types of operation desired. 1. Remove its cover by loosening the four captive cover screws. (See Figure 2.) 2. Set the RA/DA operation jumpers to the desired mode of operation. Position the operation jumpers vertically for RA (Reverse Acting) or horizontally for DA (Direct Acting). (See Figure 2.) 3. Adjust the throttling range potentiometer to desired setting. Rotate Clockwise (CW) to increase the throttling range. 5.
PAGE 9
T roubleshooting If the control system does not function properly, verify that the proper operation mode is selected on each module (DA or RA), and perform the following procedures to determine the cause of the problem: 1. Check for proper voltages on the A350P control. a. Connect a digital voltmeter (DVM) between Terminals 24V (+) and C (-) located on the A350P’s terminal block. (See Figure 2.) If an external transformer is used, select AC volts on the DVM. Verify that the voltage is between 20 and 30 VAC.
PAGE 10
3. Check the A350P control for proper operation. Note: Perform Steps 1 and 2 first. a. Reconnect the sensor to the control and re-apply power. b. Turn the throttling range and the minimum output to minimum by turning both potentiometers counterclockwise. c. Switch off the integration. d. Select the RA mode. e. Connect the DVM (+) lead to the A350P control’s Terminal SN and the (-) lead to Terminal C. If the sensor voltage is less than 1.8 VDC on model A350PS-1C or less than 2.
PAGE 11
O rdering Information Table 5: System 350 Products Item Product Code Number A350P Proportional Plus Integral Temperature Controls Description A350PS-1C Range: -30 to 130°F (-35 to 55°C) Throttling Range: 2 to 30 F° (1 to 17C°) (Includes the A99BC-25C Temperature Sensor) A350PS-2C Range: 90 to 250°F (30 to 120°C) Throttling Range: 2 to 30 F° (1 to 17C°) (Includes the A99BC-25C Temperature Sensor) A350PT-1C Range: -30 to 130°F (-35 to 55°C) Throttling Range: 2 to 30F° (1 to 17C°) (Sensor not included
PAGE 12
Specifications Product Supply Voltage Power Consumption A350P Proportional Plus Time Integral Temperature Control Y350R Power Module: Input: 120/240 VAC 50/60 Hz Output: 24 VDC, unfiltered, 10 VA External Source: 24 VAC, 50/60 Hz, Class 2 (20-30 VAC) Note: Only one supply voltage source may be used. 3.