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What control circuit options are available on KWIKstarters?

Question: What cover controls do KWIKstarters have? Why can’t I have an HOA or Pilot Light only on the larger KWIKstarters? What does the wire size have to do with the cover control options? What is the difference between remote control and without remote control?

Answer: KWIKstarters range in size from 9 to 43 amps, or 1/2 HP single phase (@ 115V) to 30HP (@460V). The cover control options for these compact starters vary from simple START and STOP pushbuttons, selector switches, and Forward-Stop-Reverse multi-function pushbuttons on reversing units.

Sprecher + Schuh offers KWIKstarters preassembled for quick turnaround, or as components. Because Sprecher + Schuh is a UL508A approved panel shop, we want to insure the best quality product reaches our customer. UL508A requires control panels to protect the control circuit in which its path is to leave the control panel assembly (remote control). To meet UL508A, a panel builder and/or user must have the proper motor branch circuit protection of common control circuits. This means, even if the short circuit protection is not directly inside the panel, such as in a KWIKstarter, the manufacturer must still consider how the panel will be protected.

Non-combination (Across-the-line) KWIKstarters are a prime example of applications utilizing common (or local) control. The compact size of KWIKstarters does not allow space inside the enclosure for fuse blocks or miniature circuit breakers for protection of the control circuit. Because of their compact size, and because the branch (short circuit) protection device is outside of the enclosure, the KWIKstater must compensate with its wire size for the maximum current expected from the outside power. UL508A sets guidelines for wire sizes as they relate to usage with remote control devices versus without remote control devices.

• “Without remote control device”- This includes a branch circuit that stays within the panel and does not rely on any remote signals, and has a maximum protective rating according to wire size. For example, START-STOP or ON-OFF push button devices that turn the circuit on or off manually at the starter cover.
• “With remote control device”- This includes a branch circuit that relies on a remote signal to control the starter, and has a maximum protective rating according to wire size. For example, a HAND-OFF-AUTO switch, Pilot RUN light or a Reset only device would be controlled from a remote location.
• See excerpts from UL508A Tables 41.1 and 41.2 for required wire sizes

  
  UL508A Table 41.1, Branch circuit protection of common control circuit without remote control device

  Control circuit wire size		Maximum protective device rating, amperes
  AWG	(mm2)
  22	(0.32)	12
  20	(0.52)	20
  18	(0.82)	25
  16	(1.3)	40
  14	(2.1)	100
  12	(3.3)	120

  UL508A Table 41.2, Branch circuit protection of common control circuit with remote control device

  Control circuit wire size		Maximum protective device rating, amperes
  AWG	(mm2)
  22	(0.32)	3
  20	(0.52)	5
  18	(0.82)	7
  16	(1.3)	10
  14	(2.1)	45
  12	(3.3)	60

  Control wire sizes used on KWIKstarter assemblies

  Contactor	Local Control	Remote Control
  CA7-9...16	#14 AWG	#14 AWG
  CA7-23	#14 AWG	#12 AWG
  CA7-30...43	#14 AWG	Requires protection
  CA7-55 and up	Requires protection device

The wire sizes used on KWIKstarters size 9A to 23A cover this requirement (see wire sizing tables above). The wire size allows for the Hand-Off-Auto control option on the cover for CAK7, CBK7 and CAKN7 KWIKstarters for the ˝ HP to 15 HP (@ 460V) range because the maximum amperes of the wire exceeds the maximum amperes of the starter. Standard START-STOP, I-O, and Pilot lights are available on all the smaller units.

However, due to the wire sizing and amperage limitations of the larger 30 to 43 amp KWIKstarter units, cover controls designed for remote control are not allowed under the UL508A standards. The larger units exclude the H-O-A, Run Light, and Reset only options because the power required to operate the remote function are not in the control of the manufacturer, and could possibly exceed the current of the installed wiring.