Switch device with non-addressable scheme for wellbore operations

A non-addressable switch device that is part of a chain of switch devices in a gun string, the non-addressable switch device comprising:

• a first switch configured to make an electrical connection between an electrical line and another non-addressable switch device of the chain of switch devices;
• a second switch configured to make an electrical connection between a detonator and the electrical line;
• a processor PA connected to the first and second switches and configured to close and open the first and second switches;
• and
• a tank circuit configured to store a voltage having a predetermined value,
• wherein the processor PA is configured to measure the predetermined value and determine, based on the measurement, whether the switch device is freshly powered up or the switch device recovered from a short circuit.

A chain of non-addressable switch devices comprising:

• plural non-addressable switch devices electrically connected to each other through an electrical line;
• and
• plural downhole tools, each hosting a corresponding non-addressable switch device,
• wherein each non-addressable switch device includes,
• a first switch configured to make an electrical connection between the electrical line and another non-addressable switch device of the chain of switch devices;
• a second switch configured to make an electrical connection between a corresponding detonator and the electrical line;
• and
• a processor PA connected to the first and second switches and configured to close and open the first and second switches,
• wherein the processor PA is configured to not use a digital address, and
• wherein the processor PA is configured to perform one of plural functions based on a corresponding pulse received along the electrical line.

A method for controlling a chain of non-addressable switch devices associated with a gun string, the method comprising:

• powering up the chain;
• sending down a first pulse, from a surface controller to a first non-addressable switch device of the chain, wherein the first pulse is associated with a first function to be performed by the first non-addressable switch device;
• performing the first function;
• sending up, from the first non-addressable switch device of the chain to the surface controller, a result of the executed function;
• sending down a second pulse from the surface controller, to close a first switch of the first non-addressable switch device of the chain to achieve electrical contact with a second non-addressable switch device of the chain;
• automatically entering the first non-addressable switch device of the chain in a sleep mode;
• and
• sending down one of the first or second pulses, from the surface controller, to the second non-addressable switch device of the chain,
• wherein only one non-addressable switch device of the chain is available for communication with the surface controller.