FDHT Spring Tester
Force Digital Hand Tester

Built to order.

The FDHT is a tension / compression tester with force measurement only. It is equipped with a high-resolution force measuring system to display current or peak force and can be fitted to perform a variety of force tests.

  • 18″ standard range
  • Standard 7″ stroke
  • Up to 4″ Ø platform (2″ standard)
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FDHT
USB and RS232 Data Connections

FDHT – Force Digital Hand Tester

 

 

 

 

 

 

 

The FDHT is a tension / compression tester with force measurement only. It is equipped with a high-resolution force measuring system to display current or peak force and can be fitted to perform a variety of force tests. Standard pull lengths of 12” can be increased with optional extended rods to up to 48” to test long parts. It has a rugged cast-aluminum and steel frame, precision rack and pinion drive with adjustments for wear and convenient hand operation to apply force and adjust length.

Includes Length Deflection Compensation

What is length deflection compensation?
All force/lengh testing devices, regardless of manufacturer, have additional deflection by the load cell and tester frame which occurs as the spring is loaded. If you buy/use a tester without deflection compensation, measurements might include significant length errors.
Spring deflection, also known as spring travel or motion, is the action of a compression spring compressing (being pushed), an extension spring extending (being pulled), or a torsion spring winding (being twisted) when a load is applied or released. This is one characteristic (spring deflection) that is measured by a Larson Systems Spring Tester.

Larson Systems has BUILT-IN Length Deflection Compensation so that the user does not have to calculate and apply length corrections. Most competitors do not have length deflection compensation.

With a Larson Systems product, forget about calculating load cell and frame deflection when testing, we’ve got you covered.

Force Specifications

Load Cell
Capacity		 Standard Resolution High Resolution*
0-100% FS 0-20% FS 20-100% FS
2 lb 0.001 lb 0.0001 lb 0.001 lb
907 g 0.2 g 0.02 g 0.2 g
8.9 N 0.002 N 0.0002 N 0.002 N
11 lb 0.005 lb 0.0005 lb 0.005 lb
5 kg 0.002 kg 0.0002 kg 0.002 kg
49 N 0.02 N 0.002 N 0.02 N
22 lb 0.01 lb 0.001 lb 0.01 lb
10 kg 0.005 kg 0.0005 kg 0.005 kg
98 N 0.05 N 0.005 N 0.05 N
66 lb 0.02 lb 0.002 lb 0.02 lb
30 kg 0.01 kg 0.001 kg 0.01 kg
294 N 0.1 N 0.01 N 0.1 N
110 lb 0.05 lb 0.005 lb 0.05 lb
50 kg 0.02 kg 0.002 kg 0.02 kg
489 N 0.2 N 0.02 N 0.2 N
200 lb 0.1 lb 0.01 lb 0.1 lb
91 kg 0.05 kg 0.005 kg 0.05 kg
890 N 0.5 N 0.05 N 0.5 N
750 lb 0.5 lb 0.05 lb 0.5 lb
340 kg 0.2 kg 0.02 kg 0.2 kg
3,336 N 2 N 0.2 N 2 N
Accuracy = ± Full Scale Resolution x 2
*Requires High Resolution Force option 050-0000-0107-00

Parts and Accessories

Tester

DescriptionPart Number 
FDHT - 2 lb Force Digital Hand Tester050-0000-0047-01Get a Quote
FDHT - 11 lb Force Digital Hand Tester050-0000-0047-02Get a Quote
FDHT - 22 lb Force Digital Hand Tester050-0000-0047-03Get a Quote
FDHT - 66 lb Force Digital Hand Tester050-0000-0047-04Get a Quote
FDHT - 110 lb Force Digital Hand Tester050-0000-0047-00Get a Quote
FDHT - 200 lb Force Digital Hand Tester050-0000-0047-05Get a Quote
FDHT - 750 lb Force Digital Hand Tester050-0000-0048-00Get a Quote

Factory and Accuracy Options

DescriptionPart Number 
High Resolution Force (10X Resolution from 0-20% FS)050-0000-0107-00Get a Quote
Micro Length Adjust with Built-in Stops (CDHT, DHT)

Micro Length Adjust with Built-in Stops

Part Number: 025-0000-0407-02

Make extremely accurate length adjustments, as well as utilize two extremely rigid compression / extension stops built right in to the assembly.

025-0000-0407-02Get a Quote
MicroAdjust Wrenchless Stop Assembly025-0000-0676-00Get a Quote
Quick Release Range Adjust Handles (200 lb Max Load)

Quick Release Range Adjust Handles

Part Number: 025-0000-0412-00

Replace your socket head cap screws with these simple handles for quick and easy range adjusting on your tester. 200 lb maximum load.

025-0000-0412-00Get a Quote
RS232 / USB output, DHT Family050-1000-0064-00Get a Quote

Accessories

DescriptionPart Number 
Spring Button Platform - 1" Ø (Hardened steel)018-0000-0914-01Get a Quote
Platforms - 4" Ø (Pair for 5/16-18 Mount)

Platforms – 4″ Ø

Part Number: 025-0000-0191-00

For testing larger diameter compression parts.

025-0000-0191-00Get a Quote
NiCad Rechargeable Battery (4-8 hr life)

NiCad Rechargeable Battery

Part Number: 025-1000-0654-00

Add an internal rechargeable battery for easy portability. A fully charged battery lasts approximately 8 hours.

025-1000-0654-00Get a Quote
Single Stop Rod

Single Stop Rod

Part Number: 025-0000-0293-00

One compression test stop only.

025-0000-0293-00Get a Quote
Double Stop Rods

Double Stop Rods

Part Number: 025-0000-0333-00

Two compression test stops, or one compression test stop and one extension test stop.

025-0000-0333-00Get a Quote
Extension Spring Swivel Wire Hook - 2 lb cap (0.030" Ø wire)

Wire Extension Hooks – 2 lb max (0.030″ Ø)

Part Number: 025-0000-0340-05

Medium duty hooks for your extension testing.

025-0000-0340-05Get a Quote
Extension Spring Swivel Wire Hook - 2 lb cap (0.050" Ø wire)

Wire Extension Hooks – 2 lb max (0.050″ Ø)

Part Number: 025-0000-0340-06

Medium duty hooks for your extension testing.

025-0000-0340-06Get a Quote
Pin Extension Hooks

Pin Extension Hooks

Light duty hooks for your extension testing. The above pictures show 025-0000-0250-05 (including the swivel mount).

Part Number Description
025-0000-0250-01 B Pin Extension Hooks – 2 lb max (Fixed Mount)
025-0000-0250-02 B Pin Extension Hooks – 66 lb max (Fixed Mount)
025-0000-0250-03 B Pin Extension Hooks – 110 lb max (Fixed Mount)
025-0000-0250-04 A Pin Extension Hooks Set – 2 / 66 / 110 lb max (Fixed Mount) Comes with protective carrying and storage case.
025-0000-0250-05 A Pin Extension Hooks Set – 2 / 66 / 110 lb max (Swivel Mount) Comes with protective carrying and storage case.
025-0000-0250-04Get a Quote
Wire Extension Hooks - 10 lb max (1/16" Ø wire)

Wire Extension Hooks – 10 lb max (1/16″ Ø wire)

Part Number: 025-0000-0340-01

025-0000-0340-01Get a Quote
Wire Extension Hooks - 66 lb max (3/32" Ø wire)

Wire Extension Hooks – 66 lb max (3/32″ Ø wire)

Part Number: 025-0000-0340-02

025-0000-0340-02Get a Quote
Wire Extension Hooks - 110 lb max (1/8" Ø wire)

Wire Extension Hooks – 110 lb max (1/8″ Ø wire)

Part Number: 025-0000-0340-00

025-0000-0340-00Get a Quote
Wire Extension Hook Set - 10 / 66 / 110 lb max. Includes protective carrying and storage case.

Wire Extension Hook Set – 10 / 66 / 110 lb max.

Part Number: 025-0000-0340-03

Wire Extension Hook Set – 10 / 66 / 110 lb max. Includes protective carrying and storage case.

025-0000-0340-03Get a Quote
Wire Extension Hooks - 1,000 lb max (5/16" Ø wire)

Wire Extension Hooks – 1,000 lb max (5/16″ Ø wire)

Part Number: 025-0000-0514-000

025-0000-0514-000Get a Quote
Wire Extension Hooks

Wire Extension Hooks

Part Number: 025-0000-0523-00

Medium duty hooks for extension testing. Protective carrying and storage case included with sets.

Part Number Description
025-0000-0340-01 Wire Extension Hooks – 10 lb max (1/16″ Ø wire)
025-0000-0340-02 Wire Extension Hooks – 66 lb max (3/32″ Ø wire)
025-0000-0340-00 Wire Extension Hooks – 110 lb max (1/8″ Ø wire)
025-0000-0340-03 Wire Extension Hook Set – 10 / 66 / 110 lb max. Includes protective carrying and storage case.
025-0000-0514-00 Wire Extension Hooks – 1,000 lb max (5/16″ Ø wire)
025-0000-0523-00 Extension Hook Set – Pin & Swivel – 10 / 66 / 110 / 1,000 lb
025-0000-0523-00Get a Quote
Machined Extension Hooks

Machined Extension Hooks

Part Number: 025-0000-0181-00

Heavy duty hooks for your extension testing.

Part Number Description
025-0000-0183-00 Machined Extension Hooks – 110 lb max
025-0000-0181-00 Machined Extension Hooks – 750 lb max
025-0000-0183-01 A Machined Extension Hook Set – 110 / 750 lb max. Includes protective carrying and storage case.
025-0000-0250-03Get a Quote
Wire Crimp Pull Fixture - Upper, 1/32 to 7/16 slot width

Wire Crimp Pull Fixture – Upper

Part Number: 025-0000-0271-00

Test your wire crimp’s integrity with LSI’s wire crimp fixtures. The upper pull fixture features 18 slots ranging from 0.031″ to 0.437″ and can accommodate up to #4 gage wire. Choose between 110 and 1,000 lb lower grip fixtures.

025-0000-0271-00Get a Quote
Wire Crimp Grip Fixture - Lower 110 lb

Wire Crimp Grip Fixture – Lower 110

Part Number: 025-0000-0274-00

Test your wire crimp’s integrity with LSI’s wire crimp fixtures. The upper pull fixture features 18 slots ranging from 0.031″ to 0.437″ and can accommodate up to #4 gage wire. Choose between 110 and 1,000 lb lower grip fixtures.

025-0000-0274-00Get a Quote
Wire Crimp Grip Fixture - Lower 1,000 lb

Wire Crimp Grip Fixture – Lower 1000

Part Number: 025-0000-0272-00

Test your wire crimp’s integrity with LSI’s wire crimp fixtures. The upper pull fixture features 18 slots ranging from 0.031″ to 0.437″ and can accommodate up to #4 gage wire. Choose between 110 and 1,000 lb lower grip fixtures.

025-0000-0272-00Get a Quote
Smooth Jaw Wire Chucks - 100 lb

Wire Chucks

Part Number: 025-0000-0193-00

For extension wire breakage testing: accepts 0.020″ to 0.312″ Ø wire.

025-0000-0193-00Get a Quote
Serrated Jaw Wire Chucks - 200 lb

Wire Chucks

Part Number: 025-0000-0193-01

For extension wire breakage testing: accepts 0.020″ to 0.312″ Ø wire.

025-0000-0193-01Get a Quote
Smooth Jaw Wire Chucks - 400 lb

Wire Chucks

Part Number: 025-0000-0193-02

For extension wire breakage testing: accepts 0.020″ to 0.312″ Ø wire.

025-0000-0193-02Get a Quote
5/16-18 M to 10-32 M/F Thread Adapter

Thread Adapters

Part Number: 018-0000-1718-00

Use differently threaded attachments with your Larson tester.

018-0000-1718-00View Product
5/16-18 M to M6 M/F Thread Adapter

Thread Adapters

Part Number: 018-0000-1718-01

Use differently threaded attachments with your Larson tester.

018-0000-1718-01Get a Quote
5/16-18 M to M4 M/F Thread Adapter

Thread Adapters

Part Number: 018-0000-1718-02

Use differently threaded attachments with your Larson tester.

018-0000-1718-02Get a Quote
Dust Cover - 18" Range Rods (FDHT, DHT, SDHT)

Dust Cover

Part Number: 059-1000-0012-00

059-1000-0012-00Get a Quote
Rubber Mounting Foot Upgrade025-0000-1310-00Get a Quote
Solid Height (Coil Bind) Protector - 2" 018-0000-4358-00View Product

Software Options

DescriptionPart Number 
SSS - Statistical & Spreadsheet Interface Software

Total Spring Inspection
The SSS software can connect to any LSI manual tester, including the DHT and the TST, and virtually any measuring device that can send data via RS232. The SSS can also accept data from the keyboard. By setting up a specific testing method, you can test your springs reliably and repeatedly and generate one comprehensive report.

Click here to view

050-0000-0075-00Get a Quote

Power Supplies

DescriptionPart Number 
Power Supply, 100-240 VAC 50-60 Hz (USA Plug)025-1000-0396-00Get a Quote
Power Supply, 100-240 VAC 50-60 Hz (International Plugs)025-1000-0396-04Get a Quote