MSTT Direct Mount Installation Guide
Applies to: Alvarado MSTT Tandem Full-Height Turnstile — Direct-to-Floor Installation Purpose: Step-by-step field installation procedure for VidIn technicians Version: 1.0 | Last Updated: February 22, 2026 Owner: John Lang
⚠️ Tandem Unit — Two Lanes, One Housing: The MSTT contains two rotor mechanisms in a single housing. It occupies significantly more floor space than a single MST. Verify the site rough-in dimensions using MTTS Measurements before any anchor work begins.
MSTT vs MST — Key Differences
If you have installed an MST Direct Mount, read this section before starting. The MSTT follows the same general process but differs in several important ways.
| MST | MSTT | |
|---|---|---|
| Lanes | 1 | 2 (tandem) |
| Rotors | 1 | 2 |
| Anchor footprint | Single unit | Wider tandem footprint — use MTTS Measurements |
| Electrical entry | Side of header | Side of header (same principle, wider unit) |
| Fire/egress wiring | Standard | Dedicated wiring diagram — see MTTS Fire Access wiring |
| Dimensions drawing | MST Right Hand Install / MST Left Hand Install | MTTS Measurements — use this, not MST drawings |
Pre-Installation Review
- Reviewed MTTS Measurements — confirmed anchor footprint dimensions
- Confirmed overhead conduit routing — electrical enters from the side of the header, not through the floor
- Confirmed overhead conduit stub location aligns with the header entry point per measurements drawing
- Confirmed floor type:
- Concrete
- Resilient Flooring (Sheet Vinyl, VCT, LVP/LVT) — ASK before drilling
- Tile & Stone — ⛔ STOP — contact PM and refer to Tile & Stone Flooring Install Guide
- Confirmed power source — MSTT requires 110VAC / 20A
Confirm with Alvarado whether the MSTT uses a single shared 110VAC feed for both rotors or requires one dedicated circuit per rotor. Update after first install.
- Confirmed access control wiring path from panel to unit — two lanes means two sets of control inputs
- Reviewed general site-prep requirements — see TURNSTILE SITE-PREP
- Reviewed MTTS Installation manufacturer manual
- Reviewed MTTS Fire Access wiring diagram — confirm egress wiring plan with EC and GC before rough-in
Layout Stage
Rough-In Dimensions
The MSTT has a significantly wider footprint than a single MST. Even a small error in anchor placement is a much bigger problem on a tandem. Pull the MTTS Measurements drawing and verify every dimension before any floor work is locked in.
- Use MTTS Measurements for all anchor locations
- Confirm anchor positions for both ends of the housing simultaneously
Electrical Routing — Header Entry
All electrical cables enter from the side of the header via overhead conduit. Cables do not come through the floor.
Coordinate with the EC before rough-in. Overhead conduit must terminate at the correct side of the header. Confirm entry side from MTTS Measurements or the installation manual.
The MSTT has two control zones (one per rotor). Label cable bundles clearly before pulling — “Rotor 1” and “Rotor 2” — so wiring inside the header stays manageable.
Cables required per rotor:
| Cable | Notes |
|---|---|
| 110VAC Power | See [!todo] above re: shared vs dedicated circuit |
| Entry Card Reader | Wiegand or OSDP — confirm reader protocol with access control sub |
| Entry Trigger | Dry contact relay output from AC panel |
| Exit Card Reader | If bidirectional (confirm with drawings) |
| Exit Trigger | If bidirectional (confirm with drawings) |
Shared across the full unit (run once):
| Cable | Notes |
|---|---|
| Fire / Emergency Egress | Single input — refer to MTTS Fire Access wiring for exact terminals |
Confirm whether fire/egress is a single shared input or requires a connection per rotor. Reference MTTS Fire Access wiring diagram and update after first install.
Mounting Stage
Floor Type Check
- For tile or stone floors, refer to Tile & Stone Flooring Install Guide before drilling.
Positioning and Drilling
- Set the MSTT unit on the floor at the marked location
- Verify the unit footprint matches the MTTS Measurements drawing
- Level the unit front-to-back and side-to-side
- The MSTT’s wider base makes leveling more sensitive — an unlevel unit will cause binding in one or both rotors
- Use supplied shims or washers; do not force the base flat against an uneven floor
- Mark anchor hole locations through the base mounting holes
- Remove unit and set aside
- Drill anchor holes per manufacturer-specified diameter and depth
- For tile or stone: see Tile & Stone Flooring Install Guide before drilling
- For all floor types: refer to Anchors Sizing and Use for anchor selection and setting procedure
- Set anchors per specifications
- Set unit back on anchors
- Level again — recheck with unit resting on the floor
- Install anchor washers and bolts — do not fully torque yet
- Tighten in a cross pattern to prevent uneven load on the base
Adjustment Stage
- Verify unit is level in both axes across the full width of the housing
- Verify both rotors spin freely by hand — no binding at any point
- If one rotor binds and the other doesn’t, the unit may not be level or the base may be stressed against an uneven floor
- Apply final anchor torque per anchor manufacturer specs — refer to Anchors Sizing and Use
Electronics Stage
⚠️ Ensure 110VAC power is OFF at the breaker before making any wiring connections.
⚠️ All access control wiring must be dry contact (voltage-free) unless the manufacturer spec explicitly states otherwise. Voltage on control inputs will damage the control board.
Power Connection
- Route 110VAC power cable(s) through the overhead conduit and into the unit via the header entry
- Connect to the power terminal block per manufacturer wiring diagram:
- Black (Line) → L terminal
- White (Neutral) → N terminal
- Green (Ground) → G terminal
Confirm exact terminal block label designations and whether power feeds to a single shared board or two separate boards. Reference MTTS Installation PDF and update after first install.
Access Control Wiring — Rotor 1
- Route Rotor 1 cable bundle through the header entry alongside power
- Connect Entry Card Reader (Rotor 1) to card reader terminal block
- Connect Entry Trigger (Rotor 1) dry contact relay to entry trigger terminals
- If bidirectional:
- Connect Exit Card Reader (Rotor 1) to exit card reader terminals
- Connect Exit Trigger (Rotor 1) dry contact relay to exit trigger terminals
Access Control Wiring — Rotor 2
- Connect Entry Card Reader (Rotor 2) to card reader terminal block
- Connect Entry Trigger (Rotor 2) dry contact relay to entry trigger terminals
- If bidirectional:
- Connect Exit Card Reader (Rotor 2) to exit card reader terminals
- Connect Exit Trigger (Rotor 2) dry contact relay to exit trigger terminals
Fire / Emergency Egress
Reference MTTS Fire Access wiring for exact terminal locations before making these connections.
- Connect fire alarm / emergency egress input per MTTS Fire Access wiring diagram
- On a fire or life safety event, both rotors will release to free egress simultaneously
- Confirm wiring is per local code and reviewed with the GC and EC
Wiring Verification
- Verify all connections — no loose strands, no exposed conductors
- Verify all cables are labeled by rotor at both ends (e.g., “Rotor 1 Entry Trigger”)
- Verify adequate slack at all termination points — no cables under tension
- Dress cables neatly inside the header — no pinching when covers are installed
Furniture Stage
Document arm/rotor component installation steps based on field experience. Reference MTTS Installation manufacturer PDF and update this section after first install. Verify whether both rotors are assembled identically or if there are tandem-specific differences.
Covers and Housings
- Install any external covers or shrouds per manufacturer instructions
- Verify no protective film or shipping material remains on any surfaces
- Verify all fasteners are snug on both ends of the housing
Power-On and Post-Installation Verification
- Turn on 110VAC power at the breaker
- Both rotors should power up and complete their self-test sequences
- Each rotor should move to its Home position independently
Document MSTT boot sequence, status indicator behavior, and any inter-rotor dependencies after first power-on observation. Reference MTTS Installation for expected behavior.
Functional Testing — Test Each Rotor Independently
- Rotor 1: Verify arm rotates freely and smoothly — no binding
- Rotor 1: Test valid credential — confirm arm releases and completes cycle
- Rotor 1: Test denied entry — confirm arm does not release
- Rotor 2: Repeat all three tests above
- Test fire/egress input — confirm both rotors release simultaneously to free egress
- If bidirectional: test exit credential and exit trigger on each rotor independently
Post-Installation Cleanup
- Wipe down stainless steel and powder-coated surfaces with a damp cloth
- Collect all packaging materials and hardware scraps
- Retain all spare anchors supplied by the reseller — do not discard
- Provide the MSTT Tandem Installation Instructions to the project or site manager
- Collect and hand over keys upon site sign-off
This guide is a working draft. Steps marked
[!todo]— header entry details, power circuit count, terminal labels, and boot sequence — should be filled in after the first MSTT installation. Updatestatustoactiveonce verified in the field.
Last updated: February 22, 2026 Owner: John Lang | jlang@vid-in.com Alvarado Technical Support: support@alvaradomfg.com | +1 (909) 591-8431 Manufacturer Docs: MTTS Installation | MTTS Fire Access wiring | MTTS Measurements