
APL-4**N Series Limit Switch Box
Installation, Operation & Maintenance Manual
Doc No. : HumG-APL4-21 Rev.1 Page 3 / 12 Valve Automation Leader, HKC
1. General
1.1. HKC APL-4 series limit switch boxes are designed to provide accurate and reliable valve position signalling
and indicating of most valves or actuators manufactured.
1.2. APL-4 limit switch boxes consist of a visual position indicator, quick-set cam ass’y, terminal strip, switch
ass’y and easy mounting bracket. Quick-set cam allows for a quick and simple hand operation in the setting
of switches.
2. Ordering Information
APL - 4 1 0 N
① ② ③
① Enclosure type of explosion proof is based on IECEx, [CNEX ITRI, --- 21 r1] :
[ Ex db IIB T6 Gb ---- 18 r0]
Enclosure type of explosion proof is based on ATEX :
[ II 2 G Ex db IIB T6 Gb --- 18 r0]
Enclosure type of explosion proof is based on KCs :
Ex d IIB T6 Gb
Enclosure type of explosion proof is based on CSA :
Cl I, Div 1, Gr C & D T6
Cl I, Zone 1, AEx d IIB T6
Ex d IIB T6
[NEMA 4X/6, IP 66/67/68 --- 17r0]
[Enclosure type of explosion proof is based on EAC :
1Ex d IIB T6 Gb X
0Ex ia IIC T6 Ga X (APL-420, APL-422 only)
Ex tb IIIC T85℃ Db ------------------------------------ 21 r1]
② Switch type
Mechanical switch
[10 : 2-SPDT (Zippy VA2-16)
11 : 3-SPDT (Zippy VA2-16)
12 : 4-SPDT (Zippy VA2-16)
13 : 2-SPST (Zippy VA2-16)
14 : 2-DPDT (Omron : DZ-10GW-1B)
15 : 2-SPDT + Potentiometer (Zippy VA2-16)
16 : 2-SPDT + Signal Unit(4~20mA) (Zippy VA2-16) ---18 r0]
Proximity switch
20 : Proximity sensor (P&F : NJ2-V3-N)
21 : Proximity sensor (Autonics : PS17-5DNU) (Except CSA)
22 : Proximity sensor (P&F : NJ4-12GM-N)
23 : Proximity sensor (P&F : NBB2-V3)
25 : Proximity sensor + Potentiometer (P&F : NJ2-V3-N)
26 : Proximity sensor + Signal Unit(4~20mA) (P&F : NJ2-V3-N)
[Reed switch
30A : Reed sensor (MS-B 301) for general purpose
30B : Reed sensor (MK21 model 85, 250V 1A max) for CSA certified use
31 : Reed sensor (MK21 model 66, 180V 0.5A max) for CSA certified use
32 : Reed sensor (MK21 model 90, 175V 0.52A max) for CSA certified use –17r0]
③ Enclosure material
N : Aluminium
3. Standard specification
Model APL-4**N
Enclosure Rating Please refer to “2. Ordering Information, ① Enclosure type”
Enclosure High grade aluminium alloy
Ambient Temperature [APL-41* : -40°C ≤ Ta ≤ +60 °C
APL-414, APL-42*, APL-43* : -20°C ≤ Ta ≤ +60 °C ---18 r0]
[-60°C ≤ Ta ≤ +60 °C @ only EAC --- 21 r1]
Cable Entries Standard : Two NPT 3/4”, or M25 for Ex type