HySecurity Hy5B Vehicle Detector (MX4621) Manuals & Support

The HySecurity Hy5B 2.0 (MX4621) is a plug-in loop detector for HySecurity Smart Touch, Smart DC and SmartCNX controllers. It plugs into a detector socket on the controller board.

It sets sensitivity for each loop, counts vehicles including tailgaters and works with the other Hy5B detectors on the board to prevent crosstalk. It draws about 35 mA, low enough for solar sites.

Identify your model

MX4621 is the current Hy5B 2.0 part number. MX4125 is the earlier Hy5B number. The Hy5B replaces the discontinued HY-5A (MX000041). On older controller software, the Hy5B runs in Hy5A emulation mode and its LED stays off.

Controller sockets: free exit, inside obstruction, outside obstruction and center loop.

Key specs

Type	Plug-in loop detector for HySecurity controllers
Controllers	Smart Touch, Smart DC and SmartCNX
Power draw	About 35 mA
Size	1-3/4 x 3-5/8 in
Software for full features	Smart DC 5.55 or higher; Smart Touch 4.54 or higher
Loop resistance	Loop plus lead-in 4.0 ohms or less; 100 megohms or more to ground
Terminals	20 to 14 AWG push terminals
Replaces	MX4125 Hy5B and MX000041 HY-5A

Manuals and documents

Installation Manual

Hy5B 2.0 Vehicle Detector Installation Instructions
D0954 · 2 pages View PDF: Hy5B 2.0 Vehicle Detector Installation Instructions (opens in a new tab)

Programming Guide

S.T.A.R.T. Software User Guide
D0049 Rev. F, 2013 · 23 pages View PDF: S.T.A.R.T. Software User Guide (opens in a new tab)

Spec Sheet

Hy5B 2.0 Spec Sheet
D0826 · 2 pages View PDF: Hy5B 2.0 Spec Sheet (opens in a new tab)

Troubleshooting

The status LED on the Hy5B shows the operating mode and loop faults.

LED off

The detector is in Hy5A emulation mode. Update the controller software with S.T.A.R.T. to use all Hy5B features.

LED flashing red

The loop is faulty. Check the loop wiring and test the loop. If the loop is good, swap the detector.

False calls

Do not leave extra loop wire coiled in the control box.
Check loop resistance and insulation to ground before you install the detector.

Common questions

MX4125 was the first Hy5B part number. MX4621 is the current Hy5B 2.0. Both plug into the same sockets.

Yes. On older software it runs in Hy5A emulation mode. For full Hy5B features, update to Smart Touch 4.54 or Smart DC 5.55 or later with S.T.A.R.T.

Yes. It is the direct replacement for the discontinued HY-5A (MX000041). No software update is needed to run it in emulation mode.

Use direct-burial loop wire such as 16 AWG XLPE, not THHN. Twist the lead-in about 6 turns per foot from the loop to the detector, and seal saw cuts with loop sealant.