Dwyer A-435-A User Manual

Model A-435-A Remote Display Tool

Specifications - Installation and Operating Instructions

Bulletin P-A-435-A

n option for Magnesense

A

ave a display would be to use a Model A-435-A remote display tool which can plug

h

nto the connector shown in Figure 1. The remote display tool has two buttons that

i
function identically to the buttons on the PCB.

CALIBRATION

NOTICE

calibration takes place. This delay is used to prevent stress related offsets on the
lower ranges.

NOTICE

adjusted by the user.

Zero Calibration

The zero calibration can be set by applying zero pressure to both the pressure
ports and pressing the zero button for 3 seconds. The display will read ZEro and
then sequence back to the home display. If the current reading is not close enough
to zero (±2%), the operation will fail and FAIL will be displayed.

®

I Differential Pressure Transmitter models that do not

I

Figure 1

There is a 5 second delay from the time the zero or span
calibration buttons is released until the time that the change in

The security level that is set in the Programming Menu Section
of the manual will determine which calibrations, if any, may be

PAN Calibration

S

he span calibration can be adjusted only after setting the zero adjustment. It must

T

e completed within 5 minutes of the last zero calibration. The span calibration

b
button will be ignored until the zero calibration is completed. Apply pressure to the
ports of the transmitter that is associated with the maximum output of the
transmitter (20 mA, 5 V, or 10 V depending on output being used). Press and hold
the span button for 3 seconds. The display will read SPAn and then sequence back

o the home display. If the span calibration is attempted before adjusting the zero

t
calibration, the FAIL error message will flash on the display. For bi-directional
ranges, separate spans can be performed for positive and negative sides of the
range. A failure will also occur if the span operation is performed too closely to the

ero point pressure.

z

isplay Error Messages

D

ovEr = The applied pressure is greater than the maximum span value causing an
Over Range Error.
UndEr = The applied pressure is less than the minimum span value causing an
Under Range Error.
FAiL = When the span or zero buttons are pressed, the pressure value is out of the
range to allow a correct setting. This may be due to a sensor failure or incorrect
pressure being applied.

Err1 = The sensor is damaged.

-rErr = Negative display value too low to display.

PROGRAMMING MENUS

Home Menu

During normal operation, the display will be in the Home Menu and will display the
current measured pressure and the engineering units.

Menu Access Security

While in the Home Menu, press and hold the Zero and Span buttons
simultaneously until SECUr appears on the display in order to access the other
programming menus. Upon releasing the buttons, the display will indicate the
current security level.

If the current security level is the security level desired (i.e. Security Level 0), press
and hold the span button for three seconds to enter the Pressure, Velocity, or Air
Flow Menu.

If the security level is not the desired level, the security level can be changed
temporarily to a lower security level or permanently to a higher level of security by
pressing the zero button. A security code will be shown on the display and it can
be changed to one of the codes listed in the below table. The span button chooses
which digit and the zero button increments the value of that digit. Pressing and
holding the span button will store the value.

Access

Yes
Yes

No
No

Edit

Menu

Yes

No
No
No

Span

Yes

No
No
No

Zero

Yes
Yes
Yes

No

Security

The level of access to the programming menus and the calibration is limited based
on the security level. The above table details the level of access for each security
level.

Level

0
1
2
3

Setting

View

Menu

000
111
222
333

DWYER INSTRUMENTS, INC.

Phone: [phone] www.dwyer-inst.com

P.O. BOX 373 • MICHIGAN CITY, INDIANA 46360, U.S.A. Fax: [phone] e-mail: [e-mail]

ode Selection / Digital Dampening Menu

M

rom the home display, pressing the span and zero button simultaneously for 3

F

econds will access the Menu Security Level. If the level is set to 0 or 1, pressing and

s

olding the span button for 3 seconds a second time will access the Mode Selection

h
Menu. The display will default to Pressure when first powered up. Pressing the zero
button will cycle to Velocity and Flow.

nce the desired Mode is displayed, pressing and holding the span button for three

O

econds will save the selected mode and display the digital dampening or averaging

s

arameter. This parameter stabilizes the output and the display by averaging the

p

eadings. There are 2.5 readings taken each second and the user can select the

r
number of seconds that they would like to average up to 240 seconds. The display
and the output will continue to update at a rate of 2.5 updates per second, but the
moving average is used for these updates.

RESSURE MODE

P

aximum Output Adjustment

M

If the Pressure Mode was selected, pressing and holding the span after adjusting the
digital dampening will enter the Pressure Mode. In this menu, the maximum output
pressure (POH) can be adjusted to any pressure between the lowest dip switch range
to the highest dip switch range. If the dip switch settings are preferred over manually

etting the range, the POH parameter can be set to off.

s

ELOCITY MODE

V
K-Factor Adjustment

If the Velocity Mode was selected, pressing and holding the span after adjusting the
digital dampening will enter the Velocity Mode and the transmitter will display the
engineering unit that has been selected by the dip switch. Pressing and holding the

pan button for three seconds will enter the K – Factor adjustment. The K – Factor

s

an be adjusted between 0.001 to 9.999. The K-Factor can be adjusted by pressing

c

he span button to select the digit and pressing the zero button to increment the value

t
of the digit. Pressing and holding the span button for three seconds will enter the
Maximum Output Adjustment parameter.

Maximum Output Adjustment

The maximum output can be equivalent to a velocity or a pressure. After adjusting the
K-Factor, the display will indicate if the adjustment is set for pressure or velocity.
Pressing the zero button will toggle between the selections. Pressing and holding the
span button for three seconds will enter the maximum output adjustment. The
maximum output can be adjusted by pressing the span button to select the digit and
pressing the zero button to increment the value of the digit. Pressing and holding the
span button for three seconds will save this value and go to the Security Update
Menu.

FLOW MODE
K-Factor Adjustment

If the Flow Mode was selected, pressing and holding the span after adjusting the
digital dampening will enter the Flow Mode and the transmitter will display the
engineering unit that has been selected by the dip switch. Pressing and holding the
span button for three seconds will enter the K – Factor adjustment. The K – Factor
can be adjusted between 0.001 to 9.999. The K-Factor can be adjusted by pressing
the span button to select the digit and pressing the zero button to increment the value
of the digit. Pressing and holding the span button for three seconds will enter the Area
Adjustment parameter.

ressing the zero button will toggle between yes and no. Yes will save the changes

P

ade to all menu items and no will discard all the changes made to all menu items.

m

f the display is set to yes, pressing and holding the span will save the menu items

I

nd return the display to the Home Position.

a

FACTORY DEFAULT PROCEDURE

n order to reset all of the menu settings back to their factory programmed values,

I

ress and hold both the span and zero buttons simultaneously for 10 seconds until

p

ACt is displayed on the LCD. Upon releasing the buttons, the unit will be factory

F

efaulted. Since resetting the transmitter will wipe out all changes, it is necessary to

d
zero (and possibly span) the transmitter before taking measurements.

MAINTENANCE/REPAIR

pon final installation of the A-435-A, no routine maintenance is required. The A-435-

U

is not field serviceable and it is not possible to repair the unit. Field repair should

A

ot be attempted and may void warranty.

n

WARRANTY/RETURN

Refer to “Terms and Conditions of Sales” in our catalog and on our website. Contact
customer service to receive a Return Goods Authorization number before shipping the

roduct back for repair. Be sure to include a brief description of the problem plus any

p

dditional application notes.

a

APPENDIX I
Air Velocity / Air Flow Calculations

Velocity is calculated using the below equation:

elocity(fpm) = K-Factor x 4004.4 x √(Diff. Press. (in of w.c.)

V

Velocity in m/s is then calculated from the equation:

Velocity(m/s) = Velocity(fpm) x 0.00508

Flow is calculated using the below equation:

Flow(cfm) = Area(Ft

3

/h) = Flow (cfm) x 1.6992

Flow (m

2

) x K-Factor x 4004.4 x √(Diff. Press. (in of w.c.)

APPENDIX II
Maximum Flow

Max Displayed Flow

Range
in w.c.

0.5

5885000

5

5885000

28

5885000

CFM

9999000
9999000
9999000

Max (K Factor x Area)

3

M

CFM Mode

/H

2037.2

644.2

272.2

3

M

/H Mode

154.5

59.9

25.3

Area Adjustment

For Flow applications, the area is multiplied by the velocity to determine the
volumetric air flow. The area will be listed in either feet or meters depending on the
dip switch settings. The units will be indicated on the display at the time of
adjustment.The area can be adjusted by pressing the span button to select the digit
and pressing the zero button to increment the value of the digit. Pressing and holding
the span button for three seconds will enter the Maximum Output Adjustment
parameter.

Maximum Output Adjustment

The maximum output can be equivalent to a flow or a pressure. After adjusting the
Area parameter, the display will indicate if the adjustment is set for pressure or flow.
Pressing the zero button will toggle between the selections. Pressing and holding the
span button for three seconds will enter the maximum output adjustment. The
maximum output can be adjusted by pressing the span button to select the digit and
pressing the zero button to increment the value of the digit. Pressing and holding the
span button for three seconds will save this value and go to the Security Update
Menu.

Security Update / Save Changes Menu

The Security Update Menu allows the security level to be set either higher or lower
than the current security level setting. This security level will be displayed the next
time the Menus are accessed from the home screen. Pressing the zero button cycles
through the security levels. Pressing and holding the span button for three seconds
accepts the new security level and gives the option to save all the menu changes.