Limits are a function of several factors.
At TD for example, your account is coded to allow certainly one-time, daily and weekly thresholds. I believe $1400 is the highest amount allowed within a single business day and I also believe it "resets" at midnight or over night once the daily batches are run.
Now, there are machine limits to consider as well. Some machines will not allow larger cash withdrawals. Some are by policy, while others are popular machines or may be getting low on cash.
Getting cash out to bank machines is expensive and it needs to be managed carefuly (the same for the in branch "machines" the tellers use to get cash). There are also floor limits to how cash can be in any specific machine/branch at any one time.
If you're using a non TD card at a TD machine, the limit should be the function of what your FI allows. I have for example, withdrawn $1000 USD from a bank machine in the US that clearly stated the limit was $200.
I'm not sure I've given you any actual useful information...