Flow Control

0254AD1A21A

Brooks Instrument Four-Channel Power Supply, Readout and Setpoint Controller

About this part

Brooks Instrument 0254AD1A21A is an exact Model 0254 secondary-electronics configuration for powering, displaying, and controlling as many as four compatible Brooks flow or pressure devices. Its order code specifies a 19-inch rack-mount kit, North American 120 VAC power cord, ±15 VDC power supply, current-pinout channel connectors with four voltage-pinout adapters, no optional RS232 cable, and standard Brooks labeling. Model 0254 supports rate setpoints, totalization, batch control, master-slave blending, valve override, self-diagnostics, and RS232 operation

Configurations vary. Verify the exact unit before choosing a replacement.

Specifications Documents (3)Photos (0)Listing history

No archived photo available

Key Facts

ManufacturerBrooks Instrument 0250 Series

Part number0254AD1A21A

Product familyConfiguration-specific

Device typeController

Configuration statusConfiguration varies

Application classIndustrial automation and process equipment

CategoryFlow Control

Specifications

Identification

Manufacturer	Brooks Instrument, LLC
Series	0250 Series secondary electronics
Base model	0254A — four-channel secondary electronics
Exact ordering code	0254AD1A21A

Exact configuration

Mounting	Rack-mount kit with 19-inch rack
Power cord	North American power cord for 120 VAC
Power-supply output option	±15 VDC
Channel pinout and adapters	Current pinout compatible with standard Brooks 0(4)-20 mA cables, plus four adapters for standard Brooks 0(1)-5 VDC cables
Communications-cable option	No optional RS232 communications cable
Labeling	Standard Brooks labeling

Architecture

Device capacity	Up to four compatible Brooks mass-flow or pressure devices
Channel connectors	Four 15-pin female D-sub channel connectors

Electrical

Power-module input	100-240 VAC, 47-63 Hz; exact configuration includes a North American 120 VAC cord
Configured power output	+15 VDC at 2.0 A and -15 VDC at 1.0 A
Controller DC input	+12 to +24 VDC required; -15 VDC permitted
Maximum channel current draw	400 mA per channel
Instrument power draw	0.8 W

Signals

Supported analog input ranges	0-5 V, 1-5 V, 0-10 V, 2-10 V, 0-20 mA, and 4-20 mA
Supported analog output ranges	0-5 V, 1-5 V, 0-10 V, 2-10 V, 0-20 mA, and 4-20 mA

Communications

Interface	RS232 for remote readout, setpoint control, programming, and data acquisition
Serial settings	9600 bit/s, 8 data bits, no parity, 1 stop bit, no flow control

User interface

Display	8-line × 40-character backlit LCD
Controls	Eight-key tactile keypad with selectable audible indication

Control functions

Process functions	Rate setpoint control, totalization, batch control, master-slave blending, valve override, and emergency stop
Valve override states	Normal, closed, or open

Diagnostics

Built-in tests

Automatic checks include system status, memory, channel input/output, communications, display, and keypad functions

Construction

Enclosure material

ABS Cycolac resin

Environment

Operating range	0 to 50 °C (32 to 122 °F), 0-95% RH non-condensing
Shipping and storage range	-40 to 85 °C (-40 to 185 °F), 0-95% RH non-condensing

Compliance

Manufacturer-listed compliance

RoHS compliant; CE; FCC Part 15 Class A and Part 68; Model 0254 listed to UL 61010 for general-purpose indoor use

Exact model-code decoding

The Brooks model-code table divides 0254AD1A21A into seven deterministic sections.

Section	Code	Manufacturer-defined meaning
I. Base model	0254A	Four-channel secondary electronics
II. Mounting	D	Rack-mount kit with 19-inch rack
III. Power cord	1	North American power cord for 120 VAC
IV. Power-supply output	A	±15 VDC
V. I/O pinout and adapters	2	Current pinout plus four voltage-pinout adapters for Model 0254
VI. Option	1	None; optional RS232 cable not selected
VII. OEM code	A	Standard Brooks labeling

Device compatibility and functions

Model 0254 is secondary electronics rather than a mass-flow controller itself.

Compatible device classesBrooks thermal mass-flow devices, Quantim Coriolis mass-flow devices, and pressure devices

Maximum connected devicesFour

Displayed variablesProcess variables and setpoints, configurable in engineering units or percent of full scale

Four-channel functionMaster-slave proportional blending is available on Model 0254

RS232 service requirements

The manufacturer manual defines the communications requirements for Model 0254.

Minimum firmware for documented serial communicationsV10.05.13 or later

Port format9600 bit/s, 8-N-1, no flow control

Protocol behaviorHalf-duplex command-and-response communication

AddressingA programmable unit address from 0 to 65535, with channel port sub-addresses

Documentation Downloads

Local PDF copies

0250 Series Data Sheet (2025-07) Local PDF download

PDF2.1 MB

0250 Series Installation & Operation Manual, Part Number 541B129AAG (2023-03) Local PDF download

PDF3.7 MB

0250 Series Quick Start Guide, Part Number 541B130AAG/C (2025-01) Local PDF download

PDF1.4 MB

Part Photos

0 images

Historical archive images for identification, labels, connectors, and condition reference, not current inventory.

Historical Listings & Prices

Historical listing data, not a current offer

Archive records1Tracked historical listing records

Historical median price$950.00Based on archived listing records

Recorded price range$950.00 - $950.00Low to high recorded listing price

Local documents3PDF copies available from Sonisys

Recorded price context

The typical recorded price range is $950.00 to $950.00. Based on 1 archived listing record; not a current offer, appraisal, or confirmed sale price.

View archived listing titles

BROOKS 0254 PN 6489 0254AD1A21A 1-4 CHANNEL MFC INTERFACE

Archived listings

Other Part Numbers & Aliases

0254AD1A21ABrooks 0254AD1A21ABrooks Instrument 0254AD1A21A