halstrup-walcher EMA 84 Instruction Manual

Instruction Manual
EMA 84 Digital
Pressure Gauge

halstrup-walcher GmbH
Stegener Straße 10

D-79199 Kirchzarten
Phone: [phone]

Fax: [phone]
E-Mail: [e-mail]

Internet: www.halstrup-walcher.com

Document 7100.002564C 07/2017

EMA 84 Instruction Manual

2

Table of Contents

1 Safety precautions .................................................................................................................. 4

1.1 Appropriate use .................................................................................................................. 4

1.2 Shipping, assembly, electrical connections and start-up ................................................... 4

1.3 Troubleshooting, maintenance, repairs, disposal .............................................................. 4

1.4 Symbols ............................................................................................................................. 5

2 Instrument description ............................................................................................................. 6

2.1 Features ............................................................................................................................. 6

2.2 Operating elements ............................................................................................................ 7

3 Start-up ................................................................................................................................... 8

3.1 Electrical connections ........................................................................................................ 8

3.2 Pneumatic connections ................................................................ ...................................... 8

3.3 Operating the instrument ................................................................................................... 8

4 Zero-point calibration .............................................................................................................. 9

5 Troubleshooting ...................................................................................................................... 9

6 Technical data ......................................................................................................................... 10

7 Dimension drawings ................................................................................................................ 11

EMA 84 Instruction Manual

3

Purpose of instruction manual

This instruction manual describes the features of the EMA 84 digital pressure gauge
and provides guidelines for its use.

Improper use of this instrument or failure to follow these instructions may cause injury
or equipment damage. Every person who uses this device must therefore read the
manual and understand the possible risks. The instruction manual, and in particular
the safety precautions contained therein, must be followed carefully. Contact the

manufacturer if you do not understand any part of this instruction manual.

Handle this manual with care:

 It must be readily available throughout the lifecycle of the instrument.
 It must be provided to any individuals who assume responsibility for operating the

instrument at a later date.

 It must include any supplementary materials provided by the manufacturer.
The manufacturer reserves the right to continue developing this instrument model

without documenting such development in each individual case. The manufacturer
will be happy to determine whether this manual is up-to-date.

Conformity

This instrument corresponds to the state of the art and meets all legal requirements
set forth in EC directives as evidenced by the CE label.

© 2006

The manufacturer owns the copyright to this instruction manual. This manual contains
data, instructions and drawings pertaining to the features and usage of this
instrument; copying this manual in part or in full or distributing it to third parties is
prohibited.

EMA 84 Instruction Manual

4

1 Safety precautions

1.1 Appropriate use

The EMA 84 is a portable, battery-powered digital pressure gauge for measuring
positive and negative differential pressures. At the heart of this precision instrument is
a pressure measurement capsule containing a membrane spring; the deflection of
this spring is then ascertained via an inductive measurement principle. Because it is
durable and easy-to-use, the EMA 84 lends itself well to maintenance work and
customer service applications for heating, air-conditioning and ventilation units, where
it can be used for monitoring filters, measuring fireplace drafts and wind pressure, etc.
Its precision and reproducibility also make the EMA 84 is highly suitable for use in
laboratory applications.

Always observe the operating requirements—particularly the permissible supply
voltage—indicated on the rating plate and in the “Technical data” section of this
manual.

The instrument may only be handled as indicated in this manual. Modifications to the
instrument are prohibited. The manufacturer is not liable for damages caused by
improper use or failure to follow these instructions. Violations of this type render all
warranty claims null and void.

1.2 Shipping, assembly, electrical connections and start-up

Only technical personnel who are appropriately trained and authorized by the
operator of the facility may assemble the instrument and set up its electrical
connections.

The instrument may only be operated by appropriately trained individuals who have
been authorized by the operator of the facility.

Specific safety precautions are given in individual sections of this manual.

1.3 Troubleshooting, maintenance, repairs, disposal

The individual responsible for the electrical connections must be notified immediately
if the instrument is damaged or if errors occur.

This individual must take the instrument out of service until the error has been
corrected and ensure that it cannot be used unintentionally.

This instrument requires no maintenance.
Only the manufacturer may perform repairs that require the housing to be opened.
The electronic components of the instrument contain environmentally hazardous

materials and materials that can be reused. For this reason the instrument must be
recycled in accordance with the environmental guidelines of the jurisdiction in
question once it has been taken permanently out of service.

EMA 84 Instruction Manual

5

1.4 Symbols

The symbols given below are used throughout this manual to indicate instances when
improper operation could result in the following hazards:

WARNING! This warns you of a potential hazard that could lead to bodily injury up
to and including death if the corresponding instructions are not followed.

WARNING: This warns you of a potential hazard that could lead to significant
property damage if corresponding instructions are not followed.

INFORMATION: This indicates that the corresponding information is important
for operating the instrument properly.

EMA 84 Instruction Manual

6

2 Instrument description

2.1 Features

The EMA 84 is a battery-operated, digital precision pressure gauge for measuring
overpressure, vacuum and differential pressure of non-aggressive gases. Operating
range is 100 Pa to 100 kPa.

Because it is robust, easy-to-use and includes an analog output, this instrument is
especially suitable for maintenance, customer service and record-keeping for heating,
ventilation and air-conditioning units.

At its heart is a pressure measurement capsule with a beryllium bronze membrane
spring, which is displaced by the pressure difference between the two chambers of
the measurement capsule. A distance measurement system converts this
displacement into an electrical signal.

EMA 84 Instruction Manual

7

2.2 Operating elements

EMA 84 Instruction Manual

8

3 Start-up

3.1 Electrical connections

Use only IEC 6 LR 51 batteries.

Open the battery compartment on the rear of the instrument by sliding down the silver
locking button. Clip the battery to the battery connector, making sure that the battery
terminals match those of the connector. Place the battery in the compartment and
replace the cover.

3.2 Pneumatic connections

Connect the EMA 84 to the pressure source at the overpressure port (+) when
measuring overpressure, at the vacuum port (-) when measuring vacuum pressure, or
at both ports (making certain to connect the + and - ports appropriately) when
measuring differential pressure.

The two valves next to the pressure ports should always be kept open (by turning all
the way to the left) when transporting the instrument or when beginning a
measurement. Turning the valves to the right will close them.

The valve of the overpressure port (+) must be closed when measuring overpressure,
and the valve of the vacuum port (-) must be closed when measuring vacuum
pressure. Both valves should be closed when measuring differential pressure.

3.3 Operating the instrument

The battery voltage must be greater than 7 V for proper operation. The battery must

be replaced if this is not the case. “LO BAT” will be displayed when the battery charge

reaches a critical level.
Turn the instrument on by flipping switch D to the up position.
Use switch C to set the desired units (kPa – mbar).
Use switch A to set the desired response time. The lowest possible response time

(“FAST” or 20 ms) is generally the best option. If, however, the pressure being

measured fluctuates to the point where a precise reading cannot be taken, the

response time can be lengthened by flipping switch A up to “MED” (0.1s) or “SLOW”

(1 s).
Proceed as outlined in section 4 (“Zero-point calibration”) if the display does not read

000 when the valves are open and/or when the pressure ports are disconnected. The
instrument will then be ready for use.

EMA 84 Instruction Manual

9

4 Zero-point calibration

The instrument has a built-in potentiometer for calibrating the zero-point, a procedure
that must be carried out with the pressure ports and/or valves open before every
measurement. This is accomplished by turning potentiometer dial B until the display
reads 000. Zero-point calibration allows the instrument to compensate for positional
errors, temperature-induced errors and long-term instrument drift. The zero point
must be calibrated with the instrument in the same position as it will be in when
operated.

The potentiometer may not be used to compensate for errors caused by overloading
the pressure measurement capsule; in other words, the zero-point can no longer be
calibrated in this case and the instrument must be returned to the manufacturer.

5 Troubleshooting

Error description

Potential cause

Corrective action

display does not appear

dead battery

install new battery
use a 9V IEC 6 LR 51 battery

instrument returns false
values

zero point has shifted

battery is low

adjust zero point
(see section 4)

display reads ‘LOW BAT,’ i.e.,

replace the battery

zero-point calibration
cannot be performed

defective pressure measurement
capsule

send the instrument to the
manufacturer for repair

EMA 84 Instruction Manual

10

6 Technical data

Measurement data

measurement ranges

0...100 Pa

0...1 kPa

0...10 kPa

0...100 kPa

overload capacity

10 x the final value of the measurement range
(for measurement ranges  20 kPa)
2 x the final value of the measurement range
(for measurement ranges > 20 kPa)

hysteresis

0.1 %

time required for adjustment

may toggle between 0.02 s, 0.2 s and 1 s

deviation from characteristic curve

setting limiting value
deviation of reference: 0,3 Pa

1 %

0.5 % option (only for measurement ranges ≥100 Pa)

0.2 % option (only for measurement ranges ≥1 kPa)

Ambient conditions

medium

air, all non-aggressive gases

operating temperature

0° C to +60° C

storage temperature

-10° C to +70° C

relative humidity

0…80 %

EMC standards

CE

conformity

declaration of conformity available upon request

Electrical data

supply voltage

9 V battery

output signal

0 to 1 V (BNC connector)

load resistance R

L

RL  2 k for an output voltage of 0.. 1 V

display

3½-place LCD, character height = 13 mm

battery life

approx. 120 hours under constant operation

Physical data

pressure port

Ø 6.5 mm for NW5 tubing
(interior tubing diameter = 5 mm)

operating position

preferably horizontal

dimensions (w x h x d)

86 x 54 x 170 mm

protection class

IP54

weight

approx. 0.75 kg, including battery

Appendix A: Parts in contact with measurement medium

 Beryllium bronze CuBe2  Araldite CY236 / HY988
 Mu metal (nickel alloy)  Loctite 242e
 Brass CuZn39Pb3  Carbonyl iron
 Aluminium AlCuMgPb / AlMg3  KEL (FPM: fluorinated rubber)
 Silicon (tubing), optional: Viton  Vepuran Vu 4457/51
 Crastin (PTBP)  UHU-Plus endfest 300 binder

EMA 84 Instruction Manual

11

7 Dimension drawings

7100 002564C_EMA84.doc 01.02.2018 Ka/Me