Workers at Eskom Rotek Industries are set to strike against labour brokers.
They are accusing brokers of not paying employees in full.
Eskom said measures have been put in place to minimise the disruption of production as some workers are expected to embark on a planned protest at its power stations from Tuesday morning.
The power utility’s Sikonathi Mantshantsha said: “It bears noting that the matters that are being raised by the protestors are already before the CCMA in which we are trying to resolve the issues in a most sustainable, legal way. We will do everything we can to reduce and minimise disruptions to electricity production.”