Abstract: A portable assessment kit for measuring metal content of an aqueous solution. The kit includes a sample container having an opening at its first end for containing a sample of the aqueous solution, a disc holder having a first end for detachably attaching the disc holder to the opening of the sample container, a pre-concentration disc for collecting metals and being arrangeable in the disc holder. The pre-concentration has a first side and a second side. The kit further includes means for pumping the sample through the opening of the sample container to the first side of the pre-concentration disc and a measurement device for measuring amount of metals in the pre-concentration disc.

Abstract: A portable assessment kit for measuring metal content of an aqueous solution. The kit includes a sample container having an opening at its first end for containing a sample of the aqueous solution, a disc holder having a first end for detachably attaching the disc holder to the opening of the sample container, a pre-concentration disc for collecting metals and being arrangeable in the disc holder. The pre-concentration has a first side and a second side. The kit further includes means for pumping the sample through the opening of the sample container to the first side of the pre-concentration disc and a measurement device for measuring amount of metals in the pre-concentration disc.

Abstract: A method and arrangement are provided for controlling electric current in a tether cable of an electrically driven mining vehicle. An indicator of an equivalent cycle current that flows through said tether cable is determined, and one or more descriptors of an actual state of dynamically changing conditions of the tether cable are obtained. A current limiting value is determined on the basis of the indicator and the descriptors, and a total amount of current is limited that the mining vehicle draws through the tether cable to a value smaller than or equal to the determined current limiting value.

Abstract: For starting an AC electric motor of a mining vehicle, it is first accelerated to a first speed with a second AC voltage provided by an onboard battery-powered inverter of the mining vehicle. A phase of a first AC voltage taken from an external grid is compared to a phase of said second AC voltage. If the phase difference between the first and second AC voltages is larger than a predetermined limit, the speed at which said inverter rotates said AC electric motor is changed. If the difference between the phases of the first and second AC voltages is smaller than the predetermined limit, a change is made from rotating the AC electric motor with the second AC voltage to rotating the AC electric motor with the first AC voltage.

Abstract: For starting an AC electric motor of a mining vehicle, it is first accelerated to a first speed with a second AC voltage provided by an onboard battery-powered inverter of the mining vehicle. A phase of a first AC voltage taken from an external grid is compared to a phase of said second AC voltage. If the phase difference between the first and second AC voltages is larger than a predetermined limit, the speed at which said inverter rotates said AC electric motor is changed. If the difference between the phases of the first and second AC voltages is smaller than the predetermined limit, a change is made from rotating the AC electric motor with the second AC voltage to rotating the AC electric motor with the first AC voltage.