Casella CEL AMS950-IS User Manual

Casella USA
17 Old Nashua Road #15
Amherst, NH 03031 USA
Email [e-mail]
Web www.casellausa.com

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The copyright in this document which contains proprietary information is vested in

CASELLA LIMITED. The contents of this document must not be used for purposes
other than for which it has been supplied or reproduced or disclosed wholly or in part
without the prior written permission of CASELLA LIMITED.

USER MANUAL

AMS950IS

INTRINSICALLY SAFE

AIRBORNE PARTICULATE MONITOR

0-200

0-2000

CASELLA LIMITED

Regent House
Wolseley Road
Kempston
Bedford
MK42 7JY
Telephone :[phone]
Facsimile :[phone]
Telex :827707
Email :[e-mail]
Web :www.casellacel.com

AMS950IS -Aerosol Monitoring System
Handbook HB3235-03

Contents.

1. Warnings....................................................... 3

2. Introduction................................................... 5

3. Principle of Operation.................................... 6

4. Operation...................................................... 7

5. Maintenance and Servicing............................ 13

6. Calibration..................................................... 14

7. Fault Finding................................................. 16

8. Specification.................................................. 17

9. Optional Accessories/Spares.......................... 18

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AMS950IS - Aerosol Monitoring System
Handbook No. HB3235-03

Warnings.

1.

The instrument should not be used without the leather case. If for some reason
it is, then the instrument is not then covered by the intrinsic safety certificate.

The charging unit can be used to operate the instrument from the mains for
extended periods. But only in an uncontrolled area.

Do not use any other charger except the one supplied by Casella. The charger
is not certified for use in explosive atmospheres. It will take approximately 12
hours to fully charge the battery.

The battery pack maybe damaged if the instrument is not switched off after
the batteries have been discharged.

If the instrument is not used for approximately one week, the batteries will be
in a discharged state.

Batteries are supplied in a discharged state

In order to obtain maximum capacity from the ni-cad battery several charge
and discharge cycles will have to be carried out.

Do not plug in the battery charger without the battery being present.

The battery module is an encapsulated unit located inside the inner enclosure
and forms an integral part of the instrument.

DO NOT pull the probe out of the clip sideways.

The warranty does not extend to cleaning or general
servicing of the instrument.

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AMS950IS -Aerosol Monitoring System
Handbook HB3235-03

No electrical repairs are to be undertaken by the customer. Failure to comply
with this will render the Intrinsic safety certificate null and void.

If there is an electrical fault in the instrument it must be returned to Casella
Ltd to repair.

The probe is made from stainless steel and contains delicate optics and
electronics, therefore the probe should not be used for any other purpose
except dust monitoring. Failure to comply will render the warranty invalid.

WARNING:- THE OPTIONAL ACCESSORIES CAN BE USED WITH THE
AMS950IS BUT ARE NOT CERTIFIED. THEREFORE CANNOT BE USED
IN A CONTROLLED AREA.

WARNING:- UNDER NO CIRCUMSTANCES SHOULD ANY OTHER
EQUIPMENT, EVEN IF IT IS IS CERTIFIED BE ATTACHED TO THE
AMS950IS AND USED IN A CONTROLLED AREA. FAILURE TO
COMPLY WITH THIS WILL RENDER THE INTRINSIC SAFETY
CERTIFICATE NULL AND VOID.

DISPOSAL OF BATTERIES:- Cells or batteries of cells must never be
disposed of by placing in a fire or incinerator , nor must they be punctured ,
crushed or otherwise mutilated or opened up in any way.
The battery must be disposed of in a safe manor, in some countries this may
envolve specialist license waste disposal companies.

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AMS950IS - Aerosol Monitoring System
Handbook No. HB3235-03

AMS950IS - AIRBORNE PARTICULATE MONITOR.

2. Introduction.

The AMS950IS aerosol monitoring system is a versatile Intrinsically safe hand held survey

instrument designed and manufactured by Casella. It combines traditional Casella quality with

modern state of the art technology.

The AMS950IS is classified to ia 11C T4, which allows the instrument to be used in explosive

atmospheres. The instrument is an ideal survey tool for portable use in a hazardous and non-

hazardous area, for both portable and fixed site surveys of airborne particulates.

The AMS950IS is able to exhibit the highest degree of sensitivity for particle sizes within the

respirable domain, while a detachable probe allows readings to be taken in relatively

inaccessible areas.

The monitor is available in two versions. One operates in the range 0.01 to 19.99mg/m3 and 0.1

to 199.9mg/m3 (0-200 version). The other 0.1 to 199.9mg/m3 and 1 to 1999mg/m3 (0-2000

version). Each instrument is factory calibrated using basic gravimetric analytical techniques. It is

supplied with a calibration unit for quick re calibration checks, which can be undertaken in

zoned areas.

The Large clear LCD instantly shows contaminant levels in mg/m3 or battery condition in volts.

The display of volts enables the user to estimate the instruments operating time before going on

site.

The AMS950IS is powered by a nickel-cadmium battery. When used in non-hazardous

atmospheres, the battery can be recharged without removal from the instrument. In this instance ,

the instrument can be run for extended periods directly from the charger to facilitate continuous

sampling.

Continuous run and charging is not possible in zoned areas, where only the AMS950IS

instrument in isolation may be used.

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AMS950IS -Aerosol Monitoring System
Handbook HB3235-03

3. Principle of Operation.

The instrument uses a beam of infra-red light projected forward into a measurement chamber.

The light is blocked from reaching the receiver by a modified Woods Horn. When dust particles

pass through the measurement chamber, the light beam is scattered forward within a narrow

angle to the receiver. The narrow angle of scatter reduces the instrument's sensitivity to

variations in the refractive index of measured particles.

The instrument is supplied (as Fig.1) in a leather case complete with a shoulder strap. The

leather case is secured to the instrument with a locking arrangement located at the back.

An allen key is provided to unlock and remove the leather case.

The instrument should not be used without the leather case. If for some reason it is, then

the instrument is not then covered by the intrinsic safety certificate.

The probe is made from stainless steel and contains delicate optics and electronics,

therefore the probe should not be used for any other purpose except dust monitoring.

Failure to comply will render the warranty invalid.

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AMS950IS - Aerosol Monitoring System
Handbook No. HB3235-03

4. Operation.

Turn the instrument on by operating the ON/OFF switch located under the leather flap. The flap

is secured by a press stud which is released by pulling it upward.

The leather flap protects the controls from the ingress of dust and therefore the instrument should

always be used with the flap secured down on the press stud.

4.1. Calibration check.

Allow approximately 5 minutes warm up time and then check the instruments zero and offset, fit

the calibration unit in position and adjust the span so the display indicates a value within the

range shown on the calibration unit. (set the range switch to the higher range and then set the

display to the upper limit shown on the calibration unit as a 3% drop in reading over a number of

hours can be expected due to temperature effects.) Then recheck zero.

4.2. Application.

Select the averaging time and range and then with the measurement chamber aperture exposed,

slowly move the probe through the aerosol or rely on natural air movement. Measurements can

be taken with the probe either attached or detached from the display unit.

The charging unit can be used to operate the instrument from the mains for extended

periods. But only in an uncontrolled area.

Controls (Fig. 2)

4.3. ON/Off switch 2 posn.

The function of this switch is self explanatory.

4.4. Charging Socket

The charging socket is a 5 way connector which under normal conditions will have the leather

case top cover over it to stop the ingress of dust.

To connect the charger unclip the leather case flap insert the charger plug and secure by

screwing the outer sleeve into the socket.

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