We are planning to buy a new switch, we have few access points with the POE+ logo on their Ethernet ports, when surveying the market for the switches we also found multiple switch models some have POE ports and others have POE+ ports. This left us wondering, if we bought switch that only has POE ports, would it be able to power up our POE+ access points?
No a POE switch does not deliver enough power to run a POE+ device.
Having plugged a Cisco 1500 AP into a normal poe switch and then struggling for a day to get a ptp link-up I can say first-hand that it is a bad idea.
The device booted up and I could log in but the Radio was stuck in reset, thinking it was a config or antenna problem, I wasted a lot of time, before finding the small message in the log, that there was not enough power to powerup the wifi module.
The similar question was asked and answered in detail here:
You have to check what's the actual requirement of device, aside the name "PoE+". The specific information about power requirement and capability to gracefully degrade service (offer less throughput in case of APs, or less power to antennas) should be clearly documented in the device technical documentation.
PoE (802.3af) provides up to 15.4W power. PoE+ (802.3at) provides up to 25.5W power. How much power does your device need? https://en.wikipedia.org/wiki/Power_over_Ethernet