No. You will have to use your health insurance first.
if primary paid more than allowed amount or if patient has primary insurance
Secondary.
The answer to this question depends on what kind of secondary insurance you have - is it a group health plan? Is it a supplement? If Medicare is primary, there are still deductibles, copays, coinsurance that would need to be satisfied by your secondary insurance. Based on your question, I'm assuming that you have a group health plan with a copayment as your secondary insurance. If so, then yes, you would pay your copayment but it would not exceed the part B deductible.
The primary /secondary payer is usually the insurance plan covering the claim
If you have insurance through your employer, and you are the policy holder,(the insurance is in your name) this insurance will be primary for you, and your spouses insurance policy will be secondary. The insurance policy thru your spouse's employer, (your spouse is the policy holder, or the insurance is in their name), this would be primary for your spouse, and your policy would be their secondary. Here's the phamplet from Medicare http://www.medicare.gov/Publications/Pubs/pdf/02179.pdf
Secondary health care providers are medical specialists with specific expertise that your primary care provider will refer you to.
Put simply, yes, you can buy travel insurance or travel health insurance without primary insurance. That's just as well, as your primary insurance may not cover you (or cover you completely) when you travel overseas.
Here's a basic example of how secondary health insurance works. You go to the doctor, he charges you $100 for the visit. Your primary insurance pays him $50 and disallows $10. The remainder of the bill, $40, then either comes to you to pay or to a secondary insurance. In most cases the secondary will pay most, if not all of the $40.
Medical providers are not required to take patients, regardless of the type of coverage.
Not necessarily; a secondary insurance policy or plan might only provide additional benefits up to the maximum that it will pay for a specified service. If both plans have rates that are similar, this might result in a small additional payment. Some secondary insurance or health plans might pay up to their maximum -- in addition to what the primary pays, which would result in a higher payment against a claim.
You could have two insurance companies pay the same medical bill or claim for a date of service through a process of subrogation where the first insurance company determined by the effective date of coverage will pay their portion of the bill and the second insurance company will pay the balance. This process is called coordination of benefits. Secondary medical insurance is a second level of insurance coverage. Under most circumstances, the two policies are independent of each other. One policy may pay for a service while the other may not. The primary policy must pay first, then the secondary. The choice of which policy is primary or secondary is established by a shared rule between insurance companies. It is not the policy holder's choice. Examples of Primary/Secondary coverage: A husband and wife both work and carry the medical insurance offered by their respective employers. The husband adds his wife to his policy. The wife adds her husband to her policy. Under most circumstances, the husband's plan would be his primary policy and his wife's plan would be his secondary policy. In like manner, the wife's plan would be her primary policy and her husband's plan would be her secondary policy. Secondary insurance should not be confused with supplemental insurance. Supplemental policies usually abide by the primary insurance guidelines. If the primary allows the charge, the supplemental will allow the charge. Most supplemental policies cover the charges you would normally pay out of pocket. For example: A Medicare supplemental policy would cover the 20% coinsurance left over after Medicare pays 80% of the allowed amount.
Medical insurance should cover any injuries substained no matter how they were caused. Health insurance is only responsible (in most cases) for what your car insurance and the third party involved's insurance does not pay. Legally, car insurance is primary over health insurance.