The picture above is of a Heathkit Model IT-1 Isolation Transformer. This instruemnt provides complete isolation of the load from the power line because there is no connection between the primary winding of the transformer and its secondary winding. The output voltage is variable from 90 to 130 VAC so that different line voltage can be duplicated to determine how the unit under test performs under adverse conditions. The instrument contains a panel meter to measure the output voltage. The instrument is fused (slow blow) at 2 Amps. The instument is rated at 100 VA continuous and 200 VA intermittant.