Which outcome occurs following a sudden loss of electrical power to a hydraulic proportional valve controlling flow rate?

💡 Explanation

When electrical power is lost, the proportional valve pilot pressure collapses immediately causing spool valve to abruptly shift back via return spring, quickly halting fluid flow. Therefore pressure spike arises rather than open default which requires sustained signal, slow closer drift which depends on mechanical deceleration, or remains in place which occurs when hydraulically locked.

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