Takeda wrote:I think that Water Container works same like mines. It means that you can plant 30(?) of them.
5 at same times only work for remote activated Ied's, claymores etc.
can someone confirm it?
The manual can confirm this

and I also tested it myself. The insurgent engineer can have 15 Ied's simultaneously. 5 mortar round IED's, 5 Mine IED's and 5 Water Container IED's
PR MANUAL wrote:Remote detonated explosives are explosives that are detonated by a remote device trigger by the individual
who placed the explosives and are generally used for ambushes and defence. Anti-Personnel Mines
(Claymores) take 5 seconds to arm after placing. When arming the detonator a sound will indicate when this
time has elapsed. If explosives are triggered prematurely, they won't explode at all. IEDs don't have this
safeguard. Most explosives have to be setup whilst in the prone position. A player can place up to 4 AP mines
and 5 C4 packs or IEDs simultaneously. Some soldiers can place two independent groups of explosives which
can be triggered individually. These explosives can all be diffused by the Combat Engineer?s wrench.
Kits: AP Mines: Conventional Forces, ARF, Militia, Hamas & Taliban Rifleman AP | Dynamite IED: ARF, Militia, Hamas &
Taliban Sapper | Mine IED: ARF, Militia, Hamas, Insurgent & Taliban Sapper Alternative | Mortar IED: ARF, Militia,
Hamas, Insurgent & Taliban Sapper Alternative & Rifleman AP Alternative | TNT IED: ARF, Militia, Hamas & Taliban
Sapper | Water Container IED: ARF, Militia, Hamas & Taliban Sapper and Engineer