Section 29 Water Level Detection and Alarm System

2901. Application

The requirements in this Section apply to tests and inspections for the type approval of water level detector and visual and audible alarm system (hereinafter called detector system) in accordance with the requirements of Pt 7 Ch 3, 1403. 1. and 3. of the Rules and Pt 7 Annex 7-6 I. of the Guidance

2902. Data to be submitted

The following reference data are to be submitted to the Society in addition to those specified in

102.

(1) Specifications of the detector system including any limitation regarding the type of cargoes for the guarantee of performance

(2) Construction drawings and explanatory documents of the working principle of the detector sys- tem

(3) Technical documents of the detector system including the manual specified in Pt 7 Annex 7-6 I.

8. of the Guidance

2903. Construction and Function

The construction and the function of the detector system is to satisfy the following requirements.

(1) To be able to adequately withstand ship vibration, ship motions, trim and heel.

(2) To be able to withstand the most severe pressure and temperature expected during working con- ditions and, for parts in contact with the liquid, to have adequate compatibility between the de-

vice and the liquid considered.

(3) The construction in addition to the above is also to be as follows:

(a) To be such that maintenance and inspection can be carried out easily and safely

(b) To have appropriate devices installed to prevent metal fittings from coming loose.

(4) The construction and function specified in Pt 7 Annex 7-6 I. 4. through 6. of the Guidance are to be provided.

(5) For the systems provided with override devices, the function specified in Pt 7 Annex 7-6 I. 6.

(5) of the Guidance is to be provided.

2904. Type test

1. The approval test is to include the following items (1) through (5) depending on the application and the type of the detector system.

(1) In addition to conformity with the requirements in 2903, confirmation of whether the test sam- ple complies with the designated specifications for finishing, construction, dimensions and parts or not

(2) Pressure test of the test specimen for a period in accordance with the following (a) through (c).

The test pressure is to be a design pressure but not less than the pressure equivalent to sea- water head of maximum depth of the space where the parts are fitted.

(a) The submerged test period for electrical components intended to be installed in ballast tanks and cargo tanks used as ballast tanks is to be not less than 20 days.

(b) The submerged test period for electrical components intended to installed dry spaces and

cargo holds not intended to be used as ballast tanks is to be not less than 24 hours.

(c)

Where a detector and/or cable connecting device (e.g. junction box, etc) is installed in a space adjacent to a cargo hold (e.g. lower stool, etc.) and the space is considered to be flooded under damage stability calculations, the detectors and equipment are to satisfy the

requirements of IP68 for a water head equal to the hold depth for a period of 20 days or

24 hours on the basis of whether or not the cargo hold is intended to be used as a ballast tank as described in (a) and (b) above.

(3) Confirmation whether the test sample performs as specified or not, under the regular installed

condition, inclining conditions of 22.5 degrees in transverse direction and 10 degrees in longi- tudinal direction at the following temperature:

(a) Parts installed outside the cargo hold: normal temperature

(b) Parts installed inside the cargo hold: maximum and minimum working temperature (Where

Guidance for Approval of Manufacturing Process and Type Approval, Etc. 2015 201

this temperature is expected within the range between 0℃ and 60℃, room temperature may be used)

(4) For the detector system installed in cargo holds, confirmation whether the test specimen detects seawater as specified or not, by merging in a test mixture of fine materials of each intended cargoes in seawater (a solution of sodium chloride having a specific gravity of 1.025 g/cm3 may be accepted as an alternative to seawater) in accordance with the followings:

(a) the test container for the cargo/water mixture is to be dimensioned so that its height and volume are such that the sensor and any filtration fitted can be totally submerged for the repeated functionality tests.

(b) the sensor and any filtration fitted that are to be arranged in the container as they would be installed in accordance with the installation instructions submitted.

(c)

(d)

(e)

(f)

The pressure in the test mixture container is to be not more than 0.02 MPa at the sensor

and any filter arrangement. The pressure may be realised by pressurisation or by using a container of sufficient height.

When the test mixture is pumped into the test mixture container, the test mixture is to be

kept in homogenized condition during the test and the effect of the pumping is not to affect the operation of the sensor and filter arrangements.

The concentration of fine materials in a test mixture is to be of minimum 50 % by weight.

In general, the type of test mixture may be limited to the followings. The smallest and largest particle size together with the density of the dry mixture used in this test is to be ascertained and recorded in the test records and the manuals required by Pt 7, Annex 7-6

I. 8. of the Guidance

(i) Minimum one type of fine mineral (dust of iron ore, coal, sand, etc. with particle size of, in general, less than 0.1 mm)

(ii) Minimum one type of grain (barleycorn, wheat, corn, etc. with particle size of, in gen- eral, greater than 3 mm)

The cargo/water mixture is to be pumped into the test container to a predetermined level

that submerges the detector and the operation of the alarm observed.

(g) The test container is then to be drained and the de-activation of the alarm condition observed.

(h) The test container and sensor with any filter arrangement are to be allowed to dry without physical intervention.

(i)

A sequence from immersion to detection is to be repeated minimum 10 times (a period of

one sequence of the test is not to be less than 30 seconds as a standard) without cleaning any filtration arrangements.

(j) Satisfactory alarm activation and de-activation at each of the ten onstrate satisfactory type testing.

consecutive tests will dem-

(5) For the electrical parts of the devices, testing as given in the following (a) through (j).

However the type tests are to comply with the requirements in 2304. 2 and, in case the ex- plosion-protected construction is required, type tests also are to comply with the requirements in Pt 6, Ch 1, 103. 2. of the Guidance.

(a) electrical power supply failure test

(b) power supply variation test

(c) dry heat test

(d) damp heat test

(e) cold test (for water ingress detectors)

(f) vibration test.

(g) insulation resistance test

(h) high voltage test

(i) inclinations tests(if the detectors contain moving parts).

(j) EMC tests( if the detector is capable of producing electromagnetic noise)

2. Additional tests other than those of the preceding 1. may be requested, where deemed necessary by the Society.

202 Guidance for Approval of Manufacturing Process and Type Approval, Etc. 2015