diff --git a/reactor-plc/backplane.lua b/reactor-plc/backplane.lua
index 44ae3ff..57dce67 100644
--- a/reactor-plc/backplane.lua
+++ b/reactor-plc/backplane.lua
@@ -118,6 +118,14 @@ function backplane.init(config, __shared_memory)
             plc_state.reactor_formed = false
         end
     end
+
+    -- detect and warn about multiple reactors
+    if #ppm.get_all_devices("fissionReactorLogicAdapter") > 1 then
+        println("startup> !! DANGER !! more than one reactor was detected! do not share reactor connections between multiple PLCs! they may not all be protected and used as configured")
+
+        log.warning("BKPLN: !! DANGER !! more than one reactor was detected on startup!")
+        log.warning("BKPLN: do NOT share reactor connections between multiple PLCs! they may not all be protected and used as configured")
+    end
 end
 
 -- get the active NIC
@@ -139,7 +147,13 @@ function backplane.attach(iface, type, device, print_no_fp)
     local sys       = _bp.smem.plc_sys
 
     if type ~= nil and device ~= nil then
-        if state.no_reactor and (type == "fissionReactorLogicAdapter") then
+        if type == "fissionReactorLogicAdapter" then
+            if not state.no_reactor then
+                log.warning("BKPLN: !! DANGER !! an additional reactor (" .. iface .. ") was connected and will not be used!")
+                log.warning("BKPLN: do NOT share reactor connections between multiple PLCs! they may not all be protected and used as configured")
+                return
+            end
+
             -- reconnected reactor
             log.info("BKPLN: REACTOR LINK_UP " .. iface)
 
@@ -250,6 +264,14 @@ function backplane.detach(iface, type, device, print_no_fp)
 
         state.no_reactor = true
         state.degraded = true
+
+        -- try to find another reactor (this should not work unless multiple were incorrectly connected)
+        local reactor, r_iface = ppm.get_fission_reactor()
+        if reactor and r_iface then
+            log.info("BKPLN: found another fission reactor logic adapter")
+
+            backplane.attach(r_iface, type, reactor, print_no_fp)
+        end
     elseif _bp.smem.networked and type == "modem" then
         ---@cast device Modem
 
diff --git a/reactor-plc/config/check.lua b/reactor-plc/config/check.lua
index 2a06a54..ff0c89c 100644
--- a/reactor-plc/config/check.lua
+++ b/reactor-plc/config/check.lua
@@ -141,6 +141,7 @@ local function self_check()
     self.self_check_msg("> check fission reactor formed...")
     -- this consumes events, but that is fine here
     self.self_check_msg(nil, reactor and reactor.isFormed(), "ensure the fission reactor multiblock is formed")
+    self.self_check_msg("> check for no more than one reactor...", #ppm.get_all_devices("fissionReactorLogicAdapter") <= 1, "there MUST be no more than one reactor connected, as a PLC uses the first one it finds, which may not always be the same one")
 
     self.self_check_msg("> check configuration...", valid_cfg, "go through Configure System and apply settings to set any missing settings and repair any corrupted ones")
 
diff --git a/scada-common/ppm.lua b/scada-common/ppm.lua
index 7e4aa30..975e529 100644
--- a/scada-common/ppm.lua
+++ b/scada-common/ppm.lua
@@ -425,26 +425,27 @@ end
 
 -- get a mounted peripheral by type (if multiple, returns the first)
 ---@nodiscard
----@param name string type name
----@return table|nil device function table
-function ppm.get_device(name)
-    local device = nil
+---@param type string type name
+---@return table|nil device, string|nil iface device and interface
+function ppm.get_device(type)
+    local device, d_iface = nil, nil
 
-    for _, data in pairs(_ppm.mounts) do
-        if data.type == name then
+    for iface, data in pairs(_ppm.mounts) do
+        if data.type == type then
             device = data.dev
+            d_iface = iface
             break
         end
     end
 
-    return device
+    return device, d_iface
 end
 
 -- SPECIFIC DEVICE ACCESSORS --
 
 -- get the fission reactor (if multiple, returns the first)
 ---@nodiscard
----@return table|nil reactor function table
+---@return table|nil reactor, string|nil iface reactor and interface
 function ppm.get_fission_reactor() return ppm.get_device("fissionReactorLogicAdapter") end
 
 -- get a modem by name
@@ -470,8 +471,8 @@ function ppm.get_wireless_modem()
 
     for iface, device in pairs(_ppm.mounts) do
         if device.type == "modem" and (emulated_env or device.dev.isWireless()) then
-            w_iface = iface
             w_modem = device.dev
+            w_iface = iface
             break
         end
     end
diff --git a/scada-common/util.lua b/scada-common/util.lua
index a5d4830..7aee4d9 100644
--- a/scada-common/util.lua
+++ b/scada-common/util.lua
@@ -24,7 +24,7 @@ local t_pack   = table.pack
 local util = {}
 
 -- scada-common version
-util.version = "1.6.0"
+util.version = "1.6.1"
 
 util.TICK_TIME_S = 0.05
 util.TICK_TIME_MS = 50