Adding unsupported device

I have successfully added a Salus ECM600 Electric Meter, which has four CT clamps measuring instantaneous power. I used the template and examples from other devices to create an external converter file. I do not fully understand in the inner workings of zigbee, but with trial and error managed to expose Link Quality and the first CT clamp power measurement.

However, I cannot figure out a way to expose the other three power channels.

Here is my external converter file:

const fz = require(‘zigbee-herdsman-converters/converters/fromZigbee’);
const tz = require(‘zigbee-herdsman-converters/converters/toZigbee’);
const exposes = require(‘zigbee-herdsman-converters/lib/exposes’);
const reporting = require(‘zigbee-herdsman-converters/lib/reporting’);
const extend = require(‘zigbee-herdsman-converters/lib/extend’);
const ota = require(‘zigbee-herdsman-converters/lib/ota’);
const e = exposes.presets;
const ea = exposes.access;

const definition = {
zigbeeModel: [‘ECM600’],
model: ‘ECM600’, // Vendor model number, look on the device for a model number
vendor: ‘Salus Controls’, // Vendor of the device (only used for documentation and startup logging)
description: ‘Electric Monitor’, // Description of the device, copy from vendor site. (only used for documentation and startup logging)
fromZigbee: [fz.metering],
toZigbee: , // Should be empty, unless device can be controlled (e.g. lights, switches).
exposes: [e.power()], // Defines what this device exposes, used for e.g. Home Assistant discovery and in the frontend
configure: async (device, coordinatorEndpoint, logger) => {
const endpoint = device.getEndpoint(1);
await reporting.bind(endpoint, coordinatorEndpoint, [‘seMetering’]);
},
ota: ota.salus,
};

module.exports = definition;

Any help would be very much appreciated.